When I go on my SUP, I take a small 1m NASA Wing kite, which has like a 3mt line and on a bar. I rarely use it, but it's there in case the wind picks up and it's great fun. Almost like street kiting.
If you're going to do any SUKing, seriously, use a 12m kite at most for your weight and make it a LEI kite so when you do loose weight, you can use it for kite surfing, even foiling later on. One kite for all. I suggest a Bow or Hybrid style kite like Cabrinha FX or NAISH Pivot. They are very stable and easy for board riding... err SUKing,