They are decent contenders as is. I think CHI would take a step back if they did this.
At least Noah is already known as a solid defender, and will undoubtedly get better under Thibs. It is so hard to replace centers like Noah. IMO, he is slightly more polished offensively than Perk, and nearly as good a defender.
He pulled down 20 rebs in a playoff game just a few months ago against CLE. And he hits his free throws at a good clip.
Carmelo as a defender? Not so sure. I know he'd get better in Thibs system, but I think if this trade happened it sets CHI back, and DEN benefits.
I can see CHI potentially beating MIA in a series, myself. They are my darkhorse team. They won't beat Boston, of course, but as their team stands right now I think they are solid talent-wise and chemistry-wise.