There is no reason for single hander to need a 43 footer. You can only sleep in one bunk at a time and use only one head at a time. As a single hander I would not want a boat much bigger than what I have. In port, I have all the accomadations I could want. At sea, I can handle everything without fancy gear.
There is a new tendency among sailors to go big. Gone are the days when a sailor would learn on a day sailor, buy a 25 footer, and finally move into the 30''s. Today, it is common for people to make a 35 or 38 footer their first boat. I think this is crazy. Bigger is not necessarily better.