With the addition of carrots on sticks, the new mode of transportation that saddled pigs offer is great! The potential combat advantages are also quite good, however I think this could be even better with a couple additions. What I suggest is adding an interface to saddled pigs (via a shift right click) that would open a small inventory, a few slots at most, and allowing the user to equip the pig with a few armor pieces, namely, a helmet and two pairs of boots, possibly more, and potentially you could add the ability to name your pig as well! This would allow the pigs to be more resilient when their riders are engaged in combat with mobs and other players, and could possibly be used to expand their functionality if they were to benefit from any enchantments on said armor as well. As a side note: setting up this interface would also be a good place to add the ability to rename other tamed mobs. This would allow us to more easily find our mounts and pets when out adventuring. Considering this it would also be a nice to be able to tether our mount when we are away from it, this could be accomplished by either a new recipe involving string and a fence post, which you can first right click then right click your pig to tether it, or by simply allowing right clicking a pig with while holding string then a fence post to tether the pig to that post.
Another suggestion would be to either raise the carrot consumption of a pig based on how much armor it is wearing, or lower the base consumption and then bring the armored pigs consumption to around what it is currently, if the former is the case, a change to how you replace the carrot might be in order as it would be fairly clunky if you had to do it once every 2 boosts or so. If it were possible, it would be a good idea to have pig armor to be subject to durability loss as well.
Some improvements to the pigs control would be a good addition. Currently it is quite easy to get stuck with the pig facing a wall or corner, as it always tries to move forward, it can't and therefore cannot turn around, this results in having to either wait for a boost to wear off and then hope the pig decides to turn, or simply switching away if not boosted and doing the same. Pigs and water do not mix very well currently, allowing control to be more effective in water even if it was slower than normal swimming would be a welcome change. Adding a way to stop the pig even while boosting would also be nice. Possibly you could add a new head armor piece that has a carrot with a stick on it and has reins attached to it. This would sacrifice some armor for the ability to better control your pig with WASD and adds the ability for you to add carrots to a pigs inventory that would automatically replenish the headpiece, you would then still have to have another carrot/stick combo in order to start a boost.
Some potential pitfalls of this idea:
Pigs become too much of a reliable form of transport/combat aid and therefore anyone who can't find a saddle is SOL (could be solved by adding other ways of getting saddles but this may make them too easy to get in less competitive environments)
saddle hoarding becomes a problem (part of above)
On competitive servers it might become a common practice to just slaughter your own pig in order to protect it from theft which is pretty gruesome (again part of above)
Might be more difficult to implement shift right clicking of entities, while having that functionality would be intuitive it might cause problems.
Let me know what you all think. Leave some comments on what you like/ don't like/ Suggestions, I'll try to add stuff to the main post as I see it.
With your idea about PVP on a pig...it just doesn't work. My apologies about not seeing the reins, I just woke up and I am tired. I still don't see it working though. You would have to make it so that the movement is IDENTICAL to the players when it one is on it, making it pretty much just bringing an extra thing to kill after the mounter dies.
No you are mistaken will you don't have to switch to move the pig you just right click with the carrot on a stick which boosts the pig then you can switch away to a sword or bow for about 40 seconds, that's actually how it currently works and has nothing to do with my suggestion, my suggestion actually expands on that by adding the helmet with carrot/reins attached idea to allow you to control it more effectively without having to switch.