There are large ones, definitely! The one we always chartered was about 30 foot and actually quite spacey... The initial plan though was to camp onshore. There are several reasons for that, first one being that the sea is very rough during that time, as you know. Last year they had to fly support goods in to some of the islands with helicopters cause the boats couldn't go out anymore... Even if we managed to camp offshore it may not be very pleasant... (here a wind and wave forecast...: http://www.windguru.cz/de/index.php?vs=1&sc=164941
) Second one is handling the kites. Im familiar with how to launch / land kites from a boat, but everything is so much easier if you can at least prepare everything onshore. The boat would imho only make sense with more than 10 riders as a support vessel, otherwise the jetski we have will be enough. Third is that things are going to be adventurous enough (getting the jetski in and out every day, finding meeting points between land crew and riders, etc pp....) and we want to spend most of our time riding, not looking for each other or saining, no? Anyhow, im very open for other opinions.