Doesn't the title sound great? I definitely think so. This is why I would like Mojang to add both of these features in 1.16.
The Lava walking enchantment could be attained by using an anvil to enchant boots with a lava walking enchantment book. You could get the book by fishing in the nether, but you might be asking how do we fish in the nether? Mojang should add a crafting recipe for a Netherite Fishing Pole. Made with Nethrite Ingots instead of Sticks. Blazing String instead of a normal String. Blazing String is made by crafting 1 String with 1 Blaze Powder making 2 Blazing String. This String is also used to repair the Netherite fishing pole by using an anvil.
Once you craft the Netherite Fishing Pole you can then cast it into the lava in the nether. You should be able to cast the Netherite Fishing Pole into lava on the overworld and in the nether. The advantage of using it in the nether being that you experience better drop rates for rare items and regular drop rates in the overworld. They should also add nether fish as an alternate food source but has to be cooked in a blast furnace to be edible.
I just thought this was a really cool change that could be made to the game for the 1.16 Nether update. Mojang if your reading this I just want you to know me and all the people that upvote this thinks this is a really cool idea. keep up the good work can't wait to see 1.16.
This is a really interesting concept. I actually went into detail with the fire walking idea on my Minecraft Ideas facebook (https://www.facebook.com/minecraft.ideas.750). Essentially, I think if it was to be added, it should work just like the frost walker I enchantment, but rather than "temporary ice" that appears under your feet, it should be obsidian. I really like the idea of fishing in the nether, but could you imagine the trouble you would get from ghasts and those pesky magma cubes that could perhaps, push you in? I like the concept though, definitely could be a cool addition.