You know what AGA is. You also compete USAG JO so you know about that.
USAG also has Xcel which is a 5 division Optional Routine Only program for gymnasts of all skill levels starting with the equivalent of JO Level 1-2. The divisions, in order, are Bronze, Silver, Gold, Platinum, and Diamond.
USAIGC is an Independent gymnastics program that is also Optional Routines Only, but they have 6 levels and they have mandatory move up scores, whereas, USAG programs do not have mandatory move up scores. The USAIGC levels are Copper, Bronze, Silver, Gold, Platinum, and Premier. Their Bronze is more like JO Level 4-5 skills.
From what I have read, TAAF is a Texas program that is similar to JO, but scored easier.
I hope this helps.