You want a cruiser instead of a bmx frame?
Why not get one of the longer BMX frames? Many bmx racers are right in the 6 foot range and that is what a lot of the bikes are designed for.
20" wheels, 21"+ top tube, longer wheelbase. Makes it fast, light, and nimble, but remains stable in the air.
and take a look around - The Free Agent bikes for racing (Eluder) can be a pretty decent value if you NEVER plan to ride freestyle, and just want to do some dirt jumping... NO PEGS EVER!
The MCS Tracer Pro may also work nicely for you.
Real BMX bikes, contrary to a lot of opinions, are not all that small. Typically though, riders don't actually sit on the seat so it is low and out of the way. The bars have enough rise to put them higher than most mountain bikes and the cranks are often longer than mountain bike cranks as it is not about clearing debris as you ride, but getting a lot of torque for speed.
There are several 24" cruisers listed on Dans site as well, but they will not respond nearly as well as the 20" bikes.