Dude you waste soooo much Δv... That aside, it's an awesome shuttle, if I have to say so myself. I pretty much built mostly shuttles since 1.3. It is what I do. And that little chugger is pretty sweet!
Oooh, yes. Sooo much Δv wasted there. Just from a design standpoint, I'd swap the SRB engine from the hawks to a titan and the orbit manoeuvrer engine to a broadsword.