For about 23 years we sailed about in Moreton Bay in Queensland
in a 23 ft Roberts sloop
. She was fantastic with a shoal draft keel
of about 18" and could get us into wonderful little hideaway spots. However, I could not live on board anymore than a couple of weeks at a time, even when young and lithe as without head
room, it was back-breaking. So I think that as long as you have adequate head
room, the length of the boat is not quite so important as a good strong hull
design. We sailed around the Whitsunday Islands in Horth Queensland
for 6 weeks, three of us in a Farr 6000, (6 metres) without even a dinghy
-- wading out to the boat at all hours hoping not to get bitten by any munchies in the water! But it was a 'pop-top' so the headroom
was not so much an issue as not having the dinghy!
Good luck I am sure you will have a great time!