(Continued from below post...)

Therefore, I'm quite confident that, outside of any modded planet types that make use of vanilla Starbound's main biomes, this mod shouldn't have any effects on modded planet types or biomes.

Furthermore, any planets that were generated before this mod's installation should be the same, assuming they've been visited. Your visitable gas giants shouldn't have any issues. (If you're still unsure, then creating a copy of your universe folder, along with whatever's inside, can allow you to return back to before this mod was installed, should you wish to uninstall it.)

@ProfileName: Let's go through what this mod does:

1. It adds all of the sub-biomes to every vanilla planet type's secondary biome arrays (except for planets with oceans). Therefore, like with any mod that adds additional secondary biomes to vanilla planet types (such as Frackin' Universe of course), it'll result in those planets being SLIGHTLY less likely to generate those other mods' secondary biomes on vanilla planets ONLY.

2. It clears the sub-biome arrays of vanilla Starbound's main biomes. However, since this mod has such a large negative priority (of -9960, as opposed to the default priority of 0), chances are that other mods that load after this mod (which should both ideally and be likely to happen) would likely add their custom sub-biomes to vanilla Starbound's main biomes as normal.

Specific question, does this mod only affect (vanilla) planet biomes? Just wanna make sure before I end up obliterating my visit-able Gas Giants with the power of more biome variety.