Thanks for you clarifications. This is all a steep learning curve, but is also very exciting. I have dreamed of having this kind of technology at my fingertips since my electronic music days in college; back then (pre-personal computer or even pre-digital keyboard) it was some Buchla modules, patch cords and a tape splicing block!!
Jer, in answer to your question...initially once I have the computer with Logic installed, the first dedicated VST (for percussion sounds) I plan to get is BFD; but from the demos I've heard, some the specialty packages from Sonicouture etc will be close behind (gamelan, hang drum, waterphone) I am also very interested in doing sampling and sound design.
This diversity in libraries is one reason why I expect I may need a broader range of platforms, beyond Logic alone. All of the software I have looked at so far, (Abelton, Celemony, Reason etc.) all seem to process sound a little differently. This is why I am seeking to to learn the best (i.e. fastest, most robust and stable) laptop configuration.