I'm 6"3', 30 inch inseam and I drive a Suzuki SX4 no problem, if you can find one. I have a taller friend and he has no problem with the SX4, either.
Suzuki is no longer operating in Canada, but depending on where you are, servicing may not be a problem. I'm in Quebec and have never had any problems.
I also have driven comfortably the Toyota Matrix (Pontiac Vibe is the twin, which I haven't driven) and the VW Golf.
All those are very solid cars.
I've driven the Chevrolet Aveo, which is very 'big' inside. (Suzuki Swift is the Aveo twin, IIRC.)
Nothing really 'cool' though
He could try the Fit without moonroof (which kills the headroom), but avoid the first generation. I test drove one over a weekend when they first came out (a rental) and it was painful.
Check the local car rental places to see what cars you can rent for a day to see which ones your son is comfortable driving in.
I seem to fit in the Mazda2/now new Yaris.