It's fairly easy to see why some people may be negatively pre-disposed toward the game, particularly when it's in a constant state of implicit comparison to Original Sin--a much more exciting title.
You know, I don't see it. Original Sin, to me, is just another RPG. A good one, sure, but hardly an exciting new concept unless you're really into co-op.
The only comparisons to Dragon Commander I can come up with are Dynasty Warriors: Empires and Total War, both series that don't have many imitators and which are both rather lacking in the role-playing-the-empire bit. Dragon Commander is not just an RTS, after all.
But perhaps there are a plethora of titles like Dragon Commander already out there and I just don't know of them.