The interior is a personal choice as to amenities and the size of them - shower, head. etc. But as far as sailing is concerned size shouldn't be an issue. With today's equipment any boat can be set up for singlehanding. Lines led aft with good clutches, good winches, and lazyjacks all make this fairly easy. In some ways the larger boat is easier to sail alone as the platform is more stable and the way forward along the sidedecks is clearer. You do have to think ahead a bit more and furling a main on a larger boat is a bit more work but that should really be the only real differences on a larger boat. Anchoring is done with a windlass on most cruisers above 30' or thereabouts so that isn't much different.
Steve and Linda Dashew sailed a 77' boat called Beowolf around the world by themselves and that included spinnaker setting and dousing - yes they are very seasoned and spinnaker setting on a 77' boat requires a LOT of thinking ahead but it can be done. Their production run of 56'to 64' Sundeers were almost all crewed by couples and several circumnavigated. Their custom boats up to 78' were also mostly sailed by couples. When a couple sail offshore you are really singlehanding on 2 different shifts. Chuck Paine's Apogee 50' design has been sailed solo by some as well. I think many could sail a boat upto 45' or so with the right rigging quite easily. Of course the maintenance budget and other costs are a lot higher and I think that is one reason why cruisers tend toward smaller boats - as I have moving from a 35' boat a few years ago to a 27' currently. But if that lottery draws my number it would be somewhere between 40' and 50'.
Last edited by mitiempo; 10-16-2009 at 06:44 PM.