I played with Google a little; if you want a full-state tour,
this is a good start. The southern loop (i.e. the parts south of Killington) is less-thought through than the upper loop, which would provide you with some rather dramatic driving. I threw a couple state parks in for good measure; Allis has a nice fire tower with good views all around, although it does involve a few miles of gravel to get there. Other than that and Lincoln Gap, I think the whole route should be paved, although parts of it may have you wondering.
If you haven't played with Google Map's ability to drag routes around, you should give it a try...it's great when you know one road to be straight and boring (e.g. Rt 7) when a parallel road (e.g. Rt 30) actually has some interesting sections.