I haven’t done it for /world teleport, but /spawn [world] is pretty much an equivalent command (not sure why /world tp exists too, but anyway), and that will be in the next update: permission nucleus.spawn.world.[lowercase world name].
World specific warps - I guess you’re just looking for a way to restrict warps to the current world. I don’t think I’ll get around to doing that for the next release, but it’s something I could look into.
If I may ask, it would be better for me to capture your ideas at Issues · NucleusPowered/Nucleus · GitHub, so if you have suggestions, could you pop them on there? They are more easily sorted by me if I can see them in a list, thanks!