If you get the right 30' boat, it may be the only boat you ever need. I know there's lots of sailors out there that believe it takes a bigger boat to go places - but the bigger the boat the less it gets sailed and the more expensive everything on it is.
Paloma is about 30', we moved down to her many years ago from a 37' boat. We've taken her on many long jaunts - Galveston to Vera Cruz, Puerto Isabella to Freeport and more - and sometimes in terrible weather. In the worst of storms, I thought, a bigger boat would be much harder to handle.
s/v Paloma, Bristol 29.9, #141
Slipped in Bahia Marina, easy access to Corpus Christi Bay and the Gulf of Mexico.