Fact is, modding is a thing, and there are already a few example mods, however I doubt that the dev will ever make take any mod and fuse it into the core game.
When it comes to some mods that are good and are already out, are:
The big booba mod (obviously)
The nun outfit mod that works with the aforementioned big booba mod (however it can't be taken off and therefore needs to be ripped off by enemies OR taken off via the forced removal cheat)
The RolePlay-S mod that adds in different level progression (and perks to go with them), weapons, magic (there is magic/apprentice armor, but it's not compatible with the big booba mod/a tit shows off to the side), mining/logging, quests
Lona reskins (for which you need a patch if you want to use them in conjunction with the Big Booba mod)
And other character reskins
A lot of these + more are linked to from the wiki under modding, others you'll have to find yourself or via the site that the RolePlay-S mod is hosted on.