Help me build two morally grey factions

I wanting to make the two primary factions of the system as morally grey as I can.

Faction 1: at first glance may appear like the good guys, it's a cluster of the "best" planets. A few Tl4s with a primary Tl5. Very earth like and prosperous. But treats the other faction like shit.

Faction 2: Has alot more planets but crap environments and living conditions. Probably rebels that come off as way too aggressive/terrorist.

Throw some ideas at me I could mix in here.