Not to get into a great debate about CF wrapped barrels but CF barrels only really save you weight when you are comparing them to the same diameter all steel barrels. You can go with something like a #4 contour all steel barrel and be within a few ounces of the same weight and save yourself a few hundred dollars.
As for velocity loss, 30-50 fps doesn't amount to squat, so if you are looking for compact and light, shorter is going to be better.