What aspect of this game do you think lacks mods or isn’t moddable

I come as a fallout modder myself, and I’m just getting started on Skyrim. Almost every aspect of Skyrim has been modded though, through the years. Is there any aspects of this game that haven’t been touched or remain vanilla because either it can’t be modded, lack of mods or it’s extremely challenging? Let me know what aspects you’d like to see modded or given more attention.