Sounds like you're going to have fun! How do you plan to track your drums? Don't forget about expandability. The good thing about say the Saffire 56 is that you get W/c, and ADAT. Is the focusrite 8 pre you have an Octopre? If so, you'd be 16 inputs off the bat!
Being able to mic and record your whole drum kit individually will open up some doors. The pres on the Saffire are fantastic, IMO. The Apollo would be a great unit, but this is the one I'd be looking at:
http://www.uaudio.com/interfaces/apollo.html