Mine is vehicle building games like Stormworks or Scrap Mechanic. It’s so much fun to shoot at your friends with your latest nuclear drone while hiding in your bunker with a better defence system than Area 51 !
I’m very curious about your fav niche game genre !
(I’m sorry for my bad English ^^')
I really like exploration era sailing games. Trade and explore. Upgrade ships etc. I’ve tried them all and none are that great. But the idea is something I really like. If something like Uncharted Waters combined with Black Flag ever came out I’d be in gaming heaven.