i think sytrus is the best of the FL bunch....
but you will quickly leave most of the built in stuff behind and start feverishly looking for other synths.
to start off, if you havent already..haha....
for bass check out---
trilogy from spectrasonics
albino 2 from......linplug...?
check out reFX, they make some nice stuff.
native instruments are near the top of the heap.....
start searchin....!!
oh, and FIRST go to kvraudio.com and get a grip of some freebies. then you wont waste any cash figuring out what you need.
peace.