Those measurements seem to be within the range of "normal" for 26" cruisers; the stays are a little short (good for that bmx life), top-tube is a bit short, too. Again, stuff i'd expect from a BMX cruiser. What's striking me as interesting is the disparity between the head-tube angle (looks steep) and the seat-tube angle (looks very slack.) Most old-school cruisers have both the head- and seat-tube angles fairly slack; the bmx cruisers were quite a bit steeper.... generally speaking, of course. The slack seat-tube with the steep head-tube angle are the opposite of characteristics we're seeing in the recent crop of hardtail mountain bikes. I'd be interested in the angles, once you pick a fork and see where it puts the frame specs.
Really cool frame...