If I were you I would say piecing something together would be your best bet.
From what it sounds like you want good performance on the strip, and decent around the corners. If that is true what I would suggest are a decent set of adjustable dampers (Illuminas at the very least, Koni yellows at the very best), and a mid range spring rate. 600 lb/in is really at the low end for any sort of sporty driving around corners, but I really will not speak for the strip since I have absolutely no experience there.
Panhard bar would be a good choice too, I think, since it will keep your car in line, which should help for a drag start as well as helping you plant more power in the corners. Lower control arms are another great place to put some money down and will help in both the straights and the turns.
I think most of the time packages are only good for accessibility and complete-ness. Not necessarily because of the quality of the pieces or how well the car will perform at the end.