1/ Crafting
2/ succeeding or failing at various tasks (but that would need a "dedicated" system, where failure is possible), like lock picking, or some sort of stuff like that.
3/ finding secrets, but I think this is already implemented.
4/ reading "one use" experience books, one could buy or find as loot;
5/ training with dummies, sparing partners,
6/ receiving lessons from masters (because obviously, PCs are novice source hunters, sent on a suicide quest with some toy Equipment...)
7/ getting badly hurt, or even dying (at least to some extend...)
8/ casting some special powerfull hard to find spells
9/ succeeding at some social checks (but there again, it requires a succeed/fail system).
it doesn't have to be 500XPs every time, but a few randomized XPs (based on intelligence, for example) could do...
You know, RPG, imagination, making the world interactive (beside picking up spoons, fish and goblets, and chain-opening barrels...).
At least, this is what I will try to do in my mod, (if the editor allows this kind of Scripting).
Sharing ideas here.
