I know Roger will jump in and provide you with some great advice. I have two comments.
1. Regarding the size of your next board, there may be one consideration that you may need to think about. Where I sail, there are big wind shadows and a "sinker" board is very difficult to manage even though it works great once in the wind. If you have a similar situation, having a board that you can uphaul can make sailing much more enjoyable. For you, that will be about 95-105 liters. I weigh 77 kg and can easily manage a 105 liter board in 25 - 30 knot winds with a 4.5 or 4.0. This is not ideal, but it works.
2. Water starts - I personally think placing both feet on the board and pulling your butt as close as possible to the board helps me water start. You will have the strength of both legs to help you stand up. I know that this is not a common way to water start, but I can manage quite well, even in very light winds sometimes (one hand on the mast and the other on the foot of the sail). However, I would first choose uphauling rather than try the "mast and sail foot" technique. The more wind you have, the less you have to rely on leg strength.
Formula 160; iSonic 111; HiFly Move 105; Tiga 263; '85 Mistral Superlight.
Maui Sails TR 11.0; 9.2; 8.4; 7.6; 6.6; Maui Sails Switch 6.0; 5.2; Maui Sails Global 4.5; 4.0.
Last edited by Ken; 27th April 2011 at 10:27 PM.