To be able to give some more immersion to the game, I'd like to create some plugins that would enable "head bobbing" while walking or running. This would require access to the game camera.
Another idea that I have in mind is drawing outlines around mouse hovered objects that you can pickup. As some objects, like branches, tend to blend into the environment so much that you can't see them, this would be a great addition. Especially for visually impaired players. This would probably require access to raycasts or at least a hover object event and get the object, then draw upon it.
Normally I'd be able to do these things quite easily with Unity based games using BepInEx, but as the game seems to use IL2CPP, that's not really feasible. It's probably too much to ask that you release the game in Mono instead, but that would definitely open up many doors to modding for those that are used to modding Unity games.