I like the Chrono's as I can kitebike and kitesurf in the same session without chancing kites, bar pressure is perfect light enough to kite all day
Blackjack, I would be using my 13m in 12 knots for the buggy, but if I was going to kitesurf as well, I would use my 18m Chrono, Airtime (I don't have a 15m ) and use the trimmer to depower it for landkiting.
Yip, over 30 knots LEI time for no stress fun. Over 45 knots 4m UNO, unless you want a speed recond then it would be a 6m R1 and a tube of no more nails to glue your balls down