Alright. I'm gonna come right out and say it. Any interface going for $250 is not gonna have great preamps in it. Good stand alone dual channel preamps start at about $500 (USD). You can get a Golden Age-Pre-73 at $300 (I've heard decent things about them), but it's only one channel.
Does your fast-track function and run well? If it does the job for recording, you could save some more money and buy an
FMR RNP. Then run the 1/4" outs of the RNP into your fast track 1/4" ins. Viola! New preamps.
The RNP has gotten good reviews by professionals, and I've heard of some of them using it alongside their $2000+ preamps.