Aside from possible vanity items any reason to visit lower level planets ?

you are right, as has been pointed out several times now.

 

When I've installed mods that require certain items in recipes that haven't been necessary in the main game, like red petals in the Bees! mod, I've travelled back to Alpha planets so I can easily farm the surface without any problems from mobs.

 

Farming alien meat. Getting kills with the bow in x sector seems impossible thus far.

 

Because they're there.

 

To crush your enemies, see them driven before you, and to hear the lamentation of their women.

 

Rape the land and salt their wives.

 

The more I think about this the dirtier it becomes... excellent job.

 

Farming monsters on t4 planets with t10 equipment for pixels, quite fast,easy and safe.

 

why simply to eradicate the local fauna of course.