Let's see what is interesting and Mac compatible.

Deep Sky Derelicts (1C Entertainment) [$7, 66% off] Sci fi rogue-like exploring derelict spaceships. Has cartoon graphics.

Exapunks (Zachtronics) [$13, 33% off] Hacking puzzle game with little robots.

BattleTech (Paradox Interactive) [$14, 66% off] Yup, still think about buying this but maybe after everything for it is finally released.

Frozen Cortex Ultimate Tier (Mode 7) [$16, 50% off] Turn-based tactical robot squads battling it out a la the old Maxis RoboSport.