i think TI basic was much easier than comodore basic; (still it really needed that extension cartridge)
https://en.wikipedia.org/wiki/TI_BASIC_(TI_99/4A)
Also it turns out that the interpreter was slow because it was written in an interpreted language, but it was good enough for simple games because they had built-in sprites.
Interesting that they have emulators/simulators for it.
http://www.99er.net/emul.shtml http://www.99er.net/win994a.shtml