You are better off with 2 boats - Gulf fishing is primarily 40+ miles in that area if you are a serious fisherman. Inshore is often 6-12 inches deep.
Kayaks are nice - don't get me wrong - I just wouldn't do the ferry kayaks around thing. Kayaks have a very limited range. You can pick up and run 5-10-20 miles in a boat. Aint doing that in a kayak. We tote layout boats around in duck season...
I'm on the east coast and breaking the rules. Running a Lund SSV-18 w 60 hp. Fish from 6 inches to about 15 miles out. It is my answer to a multi-use boat without going broke. Catch trout, snook, reds and cobia, mahi, kingfish, snapper, grouper all out of the same boat. Furthest round trip so far was about 84 miles. Folks look at me like am nuts at the boat ramp when they ask me where I'm going - say, we're headed there too (in a 25 ft rig) then I say see you in a bit.