How to get rid of barren, toxic, et al. planets?

Having played Dark Avatar for awhile, I can't seem to get over my annoyance with these planets. Alien races will colonize a planet I can't in my own territory and then get angry at me because of my influence over it. They also don't make sense in that there are plenty of other planets that are PQ 0 that look barren and are uncolonizable. Why? Are they too barren? The way the new planets were executed doesn't make logical sense and while they add to the later game, I'd much prefer to play without them.

Is there any way to mod these out? There really should be an option to be able to control the prevalence of these planets. What's the XML file that would remove these? I can't figure it out.