Morgans have such an interesting history...and opinions on them are all over the place. I own a 1969 Morgan 33 myself (not an Out Island, though) and I will attest to its strong build and seaworthiness.
From the sounds of it, an Out Island 33 may do you well. They definitely have some "boat for the buck" value, the earlier ones are built sturdy, and are considered safe, and seaworthy (as in they won''t fall apart on you, provided they are fairly well maintained!). A shoal draft will be your friend when cruising in the areas you specified. I draw 5'' and live/sail in the Sarasota / tampa area. I would say 5 is tolerable, but pushing it around here.
The downside - the OI series are nototiously NOT the greatest "sail" boats. In that they aren''t designed for performance. If you''ve got a good, reliable engine, don''t mind using it on occasion, and aren''t looking to win any friday night regattas, then you would probably be able to look past this.