So, I now have a fully usable system for games and using extended BASIC or RXB and saving.
So far I have:
The computer, obviously, the 32K RAM expansion with the TiPI (I haven't yet installed it), FinalGrom, and Ti Joysticks.
I can't think of any activity I can't do that I want now.
I'm trying to do the same with my Atari 800XL, but the peripherals are more expensive I think. Also I accidentally bought the Secam version (French) that has less colors but it works fine.
In any case, my intention really is to start programming again in TI Extended Basic.