The Pathfinder games ($3.99, $11.99) and Shadowrun: Dragonfall ($3.74) are on sale for cheap.

Hard West is only $2 and it's pretty good, X-COM style but with named characters and more story focused and a kinda quirky luck system where shots automatically miss if you have enough but it lowers your luck, getting hit gives you luck back, and you can also spend luck on abilities, so if you're behind cover and just get grazed it can work to your advantage. There's also a sequel ($8.99) that I haven't played.

X-COM 2 ($3.99) and Darkest Dungeon ($3.74) are cheap, but if you're interested in those you've probably already played them. Into the Breach ($7.49) is also good.

Wildermyth ($17.49) is an interesting little indie game. You start out with three characters who are random people who rose to the occasion to become adventures, and encounter random events that can develop them in different ways. The stories are pretty well-written, but they are self-contained, which allows them to be incorporated into your own random characters' stories, but they don't like tie together into a larger story. It's kind of a unique approach and works... ok. The combat system works well, easy to understand, but with more choices available as you level up.

Fell Seal: Arbiter's Mark ($4.49) is heavily inspired by FF Tactics but the story is forgettable and you're playing as a fantasy cop, on the plus side the gameplay is less janky and the classes are better balanced compared to FFT, imo.

Super Lesbian Animal RPG ($9.74) I haven't played but I vaguely remember hearing something good about somewhere and am thinking of picking it up.