I want to say first that I do not like the idea of potion effects on or having to do with enchantments for tools - enchantments are supposed to be upgrades of the weapons that have to do with enhancing the tool's current qualities, not adding new ones; Sharpness, Efficiency, Unbreaking, Fortune, Power...these all increase or upgrade things about the weapon itself, whether the durability, damage, speed, or block breaking (Fire Aspect and Flame are exceptions, but then again fire is not a status/potion effect). That being said, it is just my opinion, and your suggestions are actually pretty good and decently thought out.
Endurance:
A nice idea, but really this sounds more like a potion affect akin to Saturation more than an upgrade to your pick/shovel. I do see the advantage it would give in mining would be nice and not too OP, but since 1.11, hunger has been highly buffed, as AntVenom showed in a video a few months ago. So really it only saves about two seconds of eating every 5 minutes of mining or digging. Not OP, but not super useful, kind of like Smite or something.
Crushing:
So basically Auto-Smelt from Tinker's Construct? I always like this idea, but what's the point of furnaces? None of the other enchants completely replace certain functions in the game, so I feel this one is just a bit extravagant. Even in TC, you still don't get the double reward that you get from a smeltery, but as you said, it can be combined with Fortune. More thought into this than most, but also a bit OP, making gapples as common as oak trees.
Experience:
This actually isn't a bad idea, but it also depends on a few variables: maybe it is exclusive to Mending and how much does it increase XP level? I feel like maybe a 20% increase in XP but being exclusive to Mending would work out pretty well.
Critical:
Again, it depends. I think this is decent, but maybe only +1 damage, or half a heart, per level? Not super effective against diamond armor, but want to keep it balanced 
Stunning:
Here we go with the potion effects, I will try to keep my bias against the out of the way. Not bad, but maybe for less than two seconds? Also, I see your previous conversation, and it looks like you said it would be most useful in fleeing from better-geared opponents. True, but...Slowness dramatically decreases FOV, especially at level 5, meaning it would be simple to jump around your opponent, and they won't be able to hit you with their tunnel vision, meaning they might as well be AFK. This is a good concept, but may need tweaking so that it doesn't mean your opponents can't even hit you.
Recharge:
There isn't much to say about this one, it just seems natural and isn't too OP. IT would have to be a small decrease though, imagine a diamond axe with Sharpness 5 with half the cooldown of normal! Maybe each level adds 5 or 10%, so it won't be noticeable, but still a decent advantage.
Recover:
Hmm, it seems you forget the whole super-regen with full food bar from 1.10 or 1.11, I forget which. This would be nice before then, but after, it seems redundant. Maybe if you were fighting a team and didn't need to spare time for food, but they would never be able to kill you with that kind of health regen. As it is, you have to eat food to get it, making it relatively realistic. So, nice idea, but both OP and redundant.
Weakness:
Why not use a splash potion? It might be a bit inconvenient to get a brewing stand and gunpowder in a UHC match or something, but in SMP, it would be fairly easy and much better. I feel this one is similar to Endurance, we have better alternatives, so what's the point.
Sneaky:
And the reasoning behind this is what exactly? Again, interesting idea, but let's face it, nobody is ever going to sneak during matches where this would be useful. Sacrifice mobility to reduce damage...but what about shields?
Tank:
Not a bad idea, actually. It would be a distinct advantage against bow users, for sure. I don't see many problems with this, at the moment.
Escape:
But...we have Ender Pearls. It would be a bit faster of a getaway, instead of having to wait for the pearl to hit the ground, but what if your enemy teleports in front of you with lava? This might be good for escaping from better-equipped players, but...kinda depends on how well they are geared. They can still shoot you.
Healthy:
Old idea, and gapples give you absorption for that, and are actually not as rare as you might think. It would be better, as those hearts would actually regenerate (I'm assuming), but having level 2 on all armor would give you almost double health, and level 3 would more than double. It would take hard grinding to get, yes, but that's the trap many games fall into, have a hard grind to get something OP so you can keep other players from getting it. In my opinion, just OP the way you described it. I would be more comfortable with one level at +1 heart per level.
Drawback and Range:
You did credit those ideas, which is nice, and they both seem to have similar situations to Recharge. Drawback maybe has a top of -20% time, and Range maybe has +20% range (too much and the arrow might fly out of render distance :P). Good as long as they are not too strong.
Sickness:
This almost seems too OP. It would be nice if you were on a mountain and they would have a tough time reaching you or returning fire, but at close range it would still be a distinct advantage. If the duration was too short, the nausea would not distort the screen long enough to actually do anything, and if it was too long, it would give your opponent no chance of hitting you. This could be good at a very distinct timing, but I don't know how best to keep it balanced.
Homing:
Finally, you admitted that this is slightly OP, but is only really so at level 2, which is tough to get. I just feel like this isn't that bad, but it depends how it's made; if it was like Aimbot (which I HATE), then no, but if, as you said, it went to the closest entity in sights, with a certain limit depending on the level, then...I actually don't have much of a problem with that.
There you have it. I spent an hour typing this, so make sure to read it thoroughly 
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AAAA I'M SO MAD!! I had this thread all typed out, but when I pressed "Create Thread" it redirected to the login page. I hit login, and then my thread was completely gone. So I had to retype it all. Please fix this glitch, I really hate it.
Anyway, let's get to my suggestion.
Under layer 16, there is a small chance (~2%) that a block of coal ore that generates will instead generate as a diamond ore. This means that in the occasional vein of coal, there might be a diamond sticking out against the other coal ores. So if you mined 5 full veins of coal, each with 20 ores, you could expect to get only 2 diamonds (assuming all veins were under layer 16)
IMPORTANT: It's only individual coal ore blocks that generate as diamond, NOT entire veins! That would be too OP.
At y=15, there is a 0.2% chance for a diamond to spawn instead of coal.
y=14 ----- 0.4%
y=13 ----- 0.6%
.
.
y=3 ----- 2.6%
y=2 ----- 2.8%
y=1 ----- 3.0%
This suggestion is based on the misconception that diamonds can be created by putting coal under pressure. This is not really correct. Although they are both carbon based substances, coal has a lot of impurities, but diamond is pretty much pure carbon. Even if you did have a lump of carbon, you'd need to subject it to insane temperatures (~3000 C) and extreme pressures (~100000 atmospheres) to turn it into diamond. That's one thing Minecraft got right: diamonds only generate deep underground.
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Good points but I think you are overly exaggerating the effects of some of the enchantments.
Also if you don't think the Infinity enchantment is overpowered, consider the ender dragon fight. Players can easily use up 2 or 3 full stacks of arrows. To get those arrows requires a huge number of skeletons killed, or a lot of flint and feathers to craft them.
Weakness does not cause your opponent to be "unable to do damage". It takes away 2 hearts of damage per hit, but if you have full prot diamond armor on (which is the case in a lot of PVP matches), it would reduce that down to about 0.1 or 0.2 less hearts per hit. Which doesn't make a lot of difference. And don't forget, it's not just you who has these enchantments. Other players on the server would have them too. Imagine if one player had Weakening on their sword and the other one had Stunning. If the person with Stunning realizes that they are losing because the other person has Weakening, they could just hit them and run away, and they would get a 2 second head start from the stunning. They would be reasonably well matched.
Now about your statement that "any one or two of these could single-handedly decimate a person's pvp ability in one strike". Weakness does not do that. It would give you a significant advantage, I won't deny that, but it's not an instant win. The weakness enchantment would be equivalent to 2 or 3 levels of sharpness, it's not like whoever has the Weakening enchantment is instantly the winner of any pvp match. Stunning also does not do that, as explained below. The critical enchantment would act exactly like sharpness, but only on certain hits, so it's less OP than sharpness (which is not OP at all). The sharpness enchantment is a lot easier to get (because it's so common) and it acts on all hits, not just criticals. And about the Escape enchantment, you could just run away from any PVP engagements, but as soon as your opponent gets their hands on a bow, it's over. The speed gives you barely any extra protection from bow shots. Plus, it only lasts 5 seconds and only engages if someone melee hits you, so if someone is shooting you, you won't have the extra speed anyway.
And about the stunning enchantment: The only real thing you could use to your advantage with the stunning is if you see someone coming for you in (let's say sky wars, for the sake of argument) but you aren't ready for a good PVP match, you could just hit them and run away. That's the main thing it is useful for. And if you actually were in a PVP engagement, then the stunning wouldn't give you too much of an advantage. It certainly would give you some advantage, but not much. The other person can still move by jumping, even with slowness (and in most PVP matches I've seen, both players are constantly jumping).
One more thing. I just looked on Minecraft Wiki and it turns out the blindness effect also removes the ability to sprint, as well as being unable to perform critical hits. I didn't know that when I first made the list. I guess the blinding enchantment is a bit too OP.
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IT WORKS!!! THANKS!
1
Seed: -1447365248186486994
Version: 1.10.2
You spawn in a jungle, which is cool by itself, but the really great stuff is underground. Almost directly below your spawn is a system of 8 connected ravines. 4 of them form one really long mega-ravine, and the other 4 are connected off to the sides. I didn't even count ravines that weren't directly connected to other ravines, like with caves. All I can say is, wow. Amazing seed.
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seed: -1327039996
x=12824
y=244
z=5681
This seed will only work in Minecraft 1.7.