I left Miami for California years ago for the following reasons.
- The industries are all quite conservative and technophobic.
- A non-trivial percentage of businessmen are associated with money laundering and/or drugs.
- There is a paucity of talented/capable programmers.
- The local government is ridiculously corrupt.
All of these make it extremely difficult to grow any sort of tech business. I actually don't believe Miami will ever become more than a resort/vacation city; not before I die. I applaud the City of Miami government for attempting this, but I can't say I'm hopeful anything useful will be produced from this effort.
During the last "boom" in Miami I had two friends who went into business with a well-connected Latin American businessman and he eventually sold the company to a large corporation (you'd know of it). They all started with double digit ownership percentages, but after time and a ton of legal acrobatics my friends had been watered down to a pittance. They were able to pay off their car loans after the sale (multiple millions). They got scammed, in short.
So be careful in Miami and read the fine print. :)