I play Sisters.
When I don't play Sisters, I play Sisters with the worst the IG codex has to offer. Mostly infantry. Sometimes I add Inquisition to get a land raider full of DCAs, because why not, I had 500 points and didn't know what to do with them.
When I don't play either, I play Chaos. I keep telling myself one day I'll finish that daemon princess of mine, which is 320 points alone by the way, and she's accompanied by cultists, thousand sons, khorne berzerkers, terminators, raptors and warp talons, and just one heldrake.
I gave up on winning a long time ago.