Well, if you are looking for ANY refinement, the Fox body should be out of the question. Don't get me wrong, I like 'em, my '87 GT can do a hell of a lot, for just a little cash. It can be made into a corner gobbling monster, but no matter what, they are brutes.
That's part of what makes them so fun to drive. There isn't any, "Uhuh huh huh, my goodness, would you look at that cheap imitation Gucci that loser is wearing." anywhere to be found in the Fox. It's light, it's fast, and with minor mods it can really corner, but it'll make you pay for it.
I hear you on the desire for refinement, which is why I'd like a newer Cobra, but right now, that's out of the question.