Medium high aspect ratio or a foil. If you never plan to go on the water, look at ozone, flysurfer (expensive), peter lynn. For inflatos, get the 5th line or one line which help you relaunch on any terrain, like grass, where non 5th line will just slide on the grass, the 5th line will get that kite flipped over so you don't need to unrig and re-setup.
Slingshot, Naish, Cabrinha, Best and North have 5th line. SS is the best, North and Cabrinha are prone to tangle. Best is very tangle prone and crappy. North I hear wasn't very good either, but if you're not spinning or doing anything crazy, you can ride any of these no problem.