I HIGHLY recommend X if you like turn based combat. It’s my personal favorite of the series. The setting is chill beach vibes mostly, the context is pretty depressing, and there’s enough story hooks throughout the game to keep you on your toes the entire time.
XVI is pretty great if you like real time combat. If you like it at the beginning but think it’s too basic, keep playing. It gives you more to play with as you go. Great story as well. Most of the characters are really compelling.
XII is a fantastic middle ground as the combat is still then based, but you can move freely, and the gambit system is there if you want it (you can get as high level or deep as you want).
If you liked VII, try out Crisis Core. It’s the best thing to come from that world.