It's a nice touch that the music from other planets plays since you can't visit them with this mod, but it would be nice to control which tracks play. In particular I think vulcanus's music really clashes with gleba. Something like a checkbox for each planet's music would make me happy.
While I'm here, thanks for the cool mod! Some of the solutions for making basegame content accessible from gleba are very clever and must have taken some real effort.