Would center channel benefit audio only room?

"My speakers are 3 way custom utilizing a Heil AMT tweeter."

Hmm. All bets are off with such an unknown but adding another speaker to these won't elevate the soundstage (unless you put it near the ceiling).

Kal

Kr4, center channel near the ceiling is doable.

I was kidding.

Of course, you could go all the way and get a processor with Audyssey DSX to derive height channels and, even, a center.

Kal

Onhwy61, now that you have the information, you seem to have gotten lost.

I may be lost, but I don't have any problems with soundstage height!

Seriously, now that you've fleshed out your situation I haven't a clue as to what you should do.