I think I'd add every freebie that Voxengo makes, until you move up to some of their better ones (I did get GlissEQ, its a must).
Some of their free stuff is just a must-have, if it weren't free I'd buy it.
Crystal is a nicer synth than most people give it credit for, and *can* work with soundfonts even, IIRC.
http://www.greenoak.com/crystal/
If you want punchier drums check out Dominion, also from Digital Fishphones:
http://www.macmusic.org/software/releases....id/536/view/VST
There's probably a few others that don't come to mind, will add those later.