My dd has similar goals, and is not exactly math orientated, well let me clarify last year she loved math, this year after using CD pre-algebra, she has lost all of her math self-esteem and is not so sure about the whole subject. I plan on starting her in TT7 next week and using TT Pre-algebra in 8th. I know this does not seem rigorous at all, quite the opposite, but honestly - I want her to understand math and I believe that TT will help with that. Now, if after using the TT hs levels, if my dd needs additional help, I'll enroll her in a cc class to get up to speed for college, but I think at this stage of the game having her not loathe math, having her understand it and remember why it works that way far more outweighs having her do a more rigorous math program.
It won't be in the end of our world if she has to have some help later (cc class or whatever) but it would be a shame kill her dream in 7th grade. I want her to like math again, and I want her to understand what she is doing, that is my goal right now.
Chris