I think Phoenix is letting people define the argument too much, and is answering too much with "Yeah, but we have Dwight Howard") Dwight Howard has been playing with 3 other all-stars in Orlando the last few seasons, and still hasn't won a title.
There needs to be more of an argument selling Phoenix. That argument can't be centered around creating a new starting lineup. I think they'd be best off running their starting lineup out there, and saying that it's up to New Orleans to match up with you.
Dwight Howard demands a double team. If you're not doubling him with Cousins in the game, Dwight in going for 30+ per night, much like he did the "real life" Atlanta Hawks.
Jamison will bring Horford outside on defense, meaning he can't help with Horford as much. On the perimeter, Jamison is still a very effective player (and he's also a very good rebounder).
At the three, Wallace smothers Salmons, but Salmons at least should be able to stay on the perimeter a lot, drawing Wallace out and mitigating his rebounding advantage.
Eric Gordon is better than Matthews, but Matthews should at least slow him down. I mean, Gordon is a good player, but he's not a superstar; he's still a 17 ppg scorer. Think Ron Mercer with a three point shot.
Finally, at PG, Baron Davis trumps Jrue Holiday by a wide margin at this point (and I'm a big fan of Jrue).
I mean, the questions Phoenix should be asking are "Who runs / initiates New Orleans' defense, when Davis is playing good defense on Holiday?" There's no good answer to that.
Phoenix has the better constructed roster, and even though New Orleans can slow you down, they can't stop you. At some point, either Howard will go off, or New Orleans will leave your shooters open. Most likely, both.
New Orleans can throw all the stats out that it wants about defense, offensive efficiency, etc., but at the end of the day, they're asking Jrue Holiday -- an inexperienced PG who looks for his own shot -- to create for a bunch of guys who struggle creating for themselves.