Joel,
I've only ever had to have collision damage repaired, so perhaps I'm not the most qualified to answer, but here goes.
I wouldn't say they're a \"a nightmare when it comes to having bodywork done\", but what I've run into is most body shops, especially franchised ones, simply aren't interested. Especially when it comes to dealing with rust, etc. on a 30+ year old car. They want nice easy Hondas to work on, because they couldn't be bothered doing anything that requires real craftsmanship.
For your second question, it's not a difficult to get the panels straight as long as they have people who know what they're doing. When it comes to making a car symetrical, like the wheel well spaces you describe, they just chain up the body to a hydraulic puller and keep going 'till it's proper. What Ghia owners often run into, however, is the \"close enough\" attitude many shops have. I do believe, however, that every city has at least one or two shops that are qualified to return any vintage car panel to perfection through proper hammer and dolly and metal-shrinking techniques. You just have to persevere in finding these shops, and be willing to pay what they're worth.
Finally, yes. Look for the nicest car possible and repaint per your desire.