Great question, CG ... here's my own list of must have's for an acoustic guitar:
1) All-solid-wood... laminates don't resonate overtones the way solid woods do
2) Wide nut ... my large hands and thick fingers won't handle anything less than a 1.75" nut
3) I prefer a flatter 14" radius neck to a 12" radius
4) Ebony does make a better fretboard than rosewood (harder = more sustain, less dampening)
5) Cedar top on a classical ... Engleman / Adirondack / Sitka spruce top on a steel string (in that order of preference)
6) Solid build quality throughout
The price has to equate with the true value, which is why I usually shy away from "big name" brands. It doesn't matter to me if a famous guitarist endorses a particular brand (they're paid to do that), or if they have a slick marketing campaign, both of which costs will have to be built into the price.
How it sounds and how it feels will usually line up where I want them, if 1 thru 6 are in place.