Fenix Mod would probably be the best mod for the game you have in mind. It works with V1.16, has the only 3rd person camera system (to my knowledge) which
has addressed the collision issues, and it
does have RPG mod integrated into it. Fenix Mod is also
FREE, which is another reason why I would reccmmend it if you've never used a mod before. This way, if, for some reason you don't like it, it wouldn't have cost you anything.
Fenix Mod, is also currently the only available mod which has
Dark AI. Which, basically makes the enemies "smart". They won't run into walls when trying to find the player, they'll take cover, and so on.
Kravenwolf