Hello myself! I did some more searching, and I found a mod called Enemy Scaling that has what I want! You can directly modify enemy health values, by category even (so I can ramp down boss healths more than regular mobs or w/e). Got it installed, and going to test playing it tonight. Wanted to post my find for anyone else who finds this thread

I love RimWorld, and I love DRM-free, but RimWorld on GoG is a mistake.

Instead, buy RimWorld directly from Ludeon. Then you get both DRM-free files from them (to enjoy in the fallout bunker), AND a steam key (so that you can easily enjoy the metric boatloads of modding content on the steam workshop).