Whether it's the Nets or the Heat depends on large part on how severe Michael Beasley's issues turn out to be.
Heat have the natural advantage of free agents ALWAYS wanting to play in Miami. Brooklyn Nets ought to have a better chance of recruiting free agents than New Jersey, though; the lights will be shining pretty brightly. The fact that the holes the team DOES have are primarily at the positions that are usually easiest to fill is a positive as well; the best talent is in South Beach with Wade and Beasley, but there are always a lot of good wing players that can be signing in free agency, that's not alwats the case with point guards and centers.