Just so I'm clear on your plan, you are in Lake Okeechobee and planning to head
south towards the Caribbean/Bahamas/Cuba?
First, east or west out of the Lake you will have a current
assist. But if you are heading south once you hit salt water
on the Atlantic coast you will be fighting the Gulf Stream
. If you hug the coast the northerly set is usually not as bad but I have seen it 2-3 kts north just a quarter mile off the beach around West Palm.
I would probably head
south down the west coast
of FL which would put you on course to the Dry Tortugas
if you like, cruise
the Keys and beyond then as you mention, returning up the east coast
of FL with a big boost from the Stream. Down side to that route
is you will be against the wind
from the Dry Tortugas
until about halfway up the Keys. Also a beat if you plan on the Bahamas
but then that would be the case from anywhere in FL.