it would be built on its own platform so it didn't have to be so tall and flat. i would have put a straight axle in it too until they figured out how to get it not to hop and break half shafts. in all it would have been a bit smaller and lighter. the interior wouldn't have been standard charger/magnum interior. the dash would have looked more like the ebody rally dash but modernized. theres lots that could have been done. and it needed to be faster a lot faster. but when the retro mustang came out and they were selling them right off the truck chrysler was still saying retro is dead and bringing up the rear as usual.
even with those changes i wouldn't have bought one because 1) you would have to seal with a chrysler dealership and 2) you would have to deal with the service dept of a chrysler dealership when something went wrong and again when you brought it back because it wasn't fixed right the first time..
to me the challenger body has run its course and is plain out of date now. well over due for a major change.