An example:
My monitoring situation is less than optimal. I have very large monitors positioned too close to me, with rebuilt crossovers with a cuttoff frequency that's a little too high.
The result? The bass is too powerfull. Now, when I listen to commercial mixes through this setup, they sound fine of course....
However, things are different when it comes to mixing. Since I'm hearing too much bass, I tend to throw in a LOT of guitar. When it sounds optimal on my monitors, it's usually going to sound HORRIBLE when played on other sources...the guitars will completely drown out the rest of the mix. Also, the bass is kinda weak.
The solution? 1) I know this now, and don't add as much midrange. 2) I add a little more bass than I'd like. 3) I then have to check the mix on various sources....good headphones, bad headphones, tiny headphones, boom boxes, car stereos, etc.
Consider also tasks like adding reverb where levels are critical. If you're not listening to an accurate representation of the mix, it's hard to make good decisions. The only way to get an accurate representation, is to purchase good flat speakers powered by an amp that doesn't add anything unwanted to the sound.
In other words, spend some time thinking about how your monitoring situation. You mentioned the Creative/Cambridge FPS2000 system. I've played with this system before, and while it's great for gaming, it's weak for music. It sounds BIG which is COOL, but not accurate. You're going to have to spend a lot of time setting up your subwoofer and satellites. Get a mix sounding good on the FPS2000, and test it out on various other sources. Some problems will pop right out at you.
Funny thing is, one of the hardest things to do is to trust your BRAIN. I still always add too much guitar, even though I know it's going to suck...and I have to tone it down later
Anyway, I'm just an amateur and these are some of my observations. There are some good professional sources on the net. You might check the main homerecording.com BBS site and look for articles by Ed Rei (aka sonusman).
Slackmaster 2000