For the Heat, the PG has to be able to hit open 3's and outside shots. They don't have to be a creator or distributor. Makes no sense to pay a max PG to run with Wade and LeBron.
A strong center would help them a lot though. Z is over the hill, and Anthony is servicable at D but adds no offense. A guy like Marcin Gortat would be awesome in their system. It would really open up things for Bosh as well.
If the Heat do get a solid starting center, they might be the clear favorites for the next 3 or 4 years. Of course, if they win this year, they might be the favorites anyways. Can't imagine the supporting cast getting much worse then what they had to deal with this season.