Feed back isn't that terrible. It seems like you can transition pretty well. When its hard to discern whether the track has changed is a good thing. I don't know if you used an automated bpm but if you didn't props on that. Looping vocal tracks from one to the other to ensure a smooth transition makes things great also. Probably as you get more experienced you will be able to drop into another song without missing a beat. (That is an awesome achievement)

But my biggest critique is this: Use the knobs to make the mix better. Knobs are everything. The song is about to drop the bass? Flip that bass knob to zero and crank it full when the bass pumps out or reverse it when it drops out of a section.