Personally, I like low to medium grade of figure. Though I have done some plain wood, I prefer a little bit of curl or burl or whatever, but not too much. Frankly, I just don't like working super curly wood!
And when I look at original guns of the types that I like to do, they generally have low to medium grade wood too.
Whatever it is, though, it's gotta be HARD. On this, I am a major wood snob. Red maple need not apply. Walnut and cherry must be selected carefully.