Suggestion: Carry mobs, leg/arm collision
I suggest adding two optional features for additional immersion and interaction with the world.
First idea: add collision to arms and legs. This way you can push entities more accurately with your limbs. I was prompted to do this by adding FBT, but even without it it would be nice to push entities at least with your hands.
Second idea: add the ability to carry small entities in your hands. For example, a pig or a chicken will require two hands, while a salmon will take only one hand. This is useful both for fun and for placing mobs in the right places without a leash or for placing them in difficult places (for example, putting fish in an aquarium (on waterlogged chests))
Also imagine catch ghast fireball with your hands and throw it into your friend or back to the ghast x3