They call it a 2+2 for a reason...those back two seats are meant for occasional use. So I don't blame you for not feeling like the car makes sense.
I've got a Cobalt right now...and it's a sedan -- but I've been in the coupe, and there's not a whole lot difference. Anyways, I've learned to just deal with it. I pull the seat up a couple clicks more than I'd like, and we just...deal with it. So for me, personally -- having a couple extra inches of rear seat room isn't worth making the car any larger.
Especially not as large as the Challenger.
Have you checked out a G8? It seems you really want those rear seats....