I can honestly say that I am not a cam expert by any means.
The main problem you will get when asking online what kind of cam you should go with is that you will get 23984721498767210349671209473457 answers. (ok... maybe I exaggerated a little, but the point still stands)
basically what you are wanting is a streetable, but decently powerful car.
as far as the 30k spring change, ive heard of it, but never seen it in practice. if you upgrade the springs to a good quality/capability when you do the swap, you shouldnt have any problems.
one of the best ways to find the best cam for you is to call up nearly every cam manufacturer and tell them what you want to do, and I can guarantee you, every answer you get will be different.
that being said. Comp Cams and Mast Motorsports already have some trick cams for both the LS3 and the L99 available.
http://mastmotorsports.com/
http://www.compcams.com/DefaultWide.asp