I'm totally with you on eliminating trips from truck to beach.
If the wind is strong and I'm packing smaller kites, I can put everything I need into my large 17m kite bag (with 17m kite removed). I can pack 2 small kites plus bar, pump, wetsuit and other junk into my large light wind kite bag.
A hockey bag is a good idea, too. If all you want is a shoulder strap duffel, they are cheap cheap at the chain stores and some are really large.
My challenge comes with multiple boards. I can manage one big bag plus 2 boards in a single trip, but sometimes another board (directional) would be good to have. ....... feelin' like a donkey just sittin' here...