It'd be nice if there was a way for mods to either have certain vars that can be set via the mod menu or if you added code so that modders could make their own UIs. I just thought it'd be a nice idea, since I recently made my own mod and it'd just be really nice since then the people that download your mod would be able to configure stuff they do/don't like on their own without you having to make multiple mods just for a simple change.
As for how this could be implemented... I gotta say I don't really have much experience with UIs and all that jam, but I think you might be able to (if you were going for that route) make it so you could add new actions inside rules files that can create either sliders, text boxes, check boxes or other UI elements the user can configure in the mod menu (as in the menu where you actually enable mods).
#Mod menu gui (or mod settings)
glacial glacier
glossy cairn