I use Stormdrum with the Kontakt player by Native Instruments (managed to pick it up free) but there's a more updated version of it available now. It's quite expensive though, but it's a fantastic library. I also have Symphobia (and I won't discuss how I obtained that one) which is absolutely amazing, but it's like $1300+. A lot of game and movie composers supposedly use it, I can't argue with its quality. It's roughly a 17gb library.
The FPC plugin in Fruityloops is actually a great plugin, but the stock samples are terrible. FL Studio 9 has more drum kits to choose from, but they're all pretty mediocre. You can create your own kit if you have some custom samples, that's what I do. I don't think you'd need any other drum machine than FPC. The problem is that finding good samples can be really difficult. I found some decent samples at freesound.org, but you need to create a free account in order to download files.
The pluck that came in sounds like the Plucked! plugin. I'd stay away from it since it's pretty static. You also have some distortion in the high frequencies when the stronger pads come in. You gotta make some use of the Parametric EQ 2 effect plugin to get rid of such things, especially if you're dealing with low frequencies (bass and low bass).
Some VSTs I use are the following (none of which are free):
z3ta+
Absynth 4
FM8
Blue
Renegade
Predator
Discovery V2
Albino 3
Surge
Vanguard
Toxic Biohazard (Demo version comes with FL Studio, but it creates a weird sound occasionally if you don't have the full version)
Synplant (Incredibly intuitive plugin, I highly recommend it)
Anyway, all the recommendations here are good. Fruity Loops may seem weak because of the stock content, but when you match it up with awesome libraries and plugins, it's a great program.