If this team ever starts winning consistently again, there won't be a problem with attendance anywhere north of the Dade-Broward line. They could build a 100,000 seat stadium in West Broward and fill it easily. ALL of S.Fla. would rally around the team. Best case.
If this team stays mediocre and somehow got stuck in an urban setting, nice try getting folks to drive from Sunrise or Weston or anywhere north of Miami Gardens Drive to venture down there for a game. Worst case.
It would be interesting to see just how FEW fans the heat draws from outside Dade County. Or even how few drive up from South Dade. The heat fan base is a niche fan base centered on urban Miami and Miami Beach. Different demos.