hey there , I was kind of in the same boat for awhile. I do alot of rock and metal but I like to do the whole "one man band" thing. Making my own drum beats, adding synths, other instruments etc. I currently use a Firestudio w/ Cubase Studio 4 and Rewire using Reason 4. I find it great for me and it never really limits my creativity. It just comes down to recognizing sounds and being able to search through the library of sounds. If you like having a module and a keyboard than go with that, but for me personally, I like having all my sounds software based so I can search and switch when needed, with a MIDI controller. And then I can also record my own electric guitar or bass or any other sounds, etc.

I will suggest that Reason 4 is a pretty good overall package, I got a student discount so it was only about $300 for me. That route may leave you with extra money, and virtual instruments and packages could leave you with plenty of choices. I will admit that some sounds in Reason are very.... Dry. They are very recognizable. You may find yourself listening to music and saying "That is so Reason..." after opening up to it for awhile. Maybe you'll spend $250 on a virtual instrument piano and that leaves you with money to spend on something else.

I actually just posted in a recent topic about how I was looking for more orchestra sounds because Reason 4 wasn't doing it completely for me. So I guess you have to try things out, experiment, and expand your software, and yes, I know, it's a big investment!