New bikes are going to be stiff, maybe you should try sitting on a used one to compare seat hieght after break-in? I'm 5'7'' also, with a 32'' inseam, the only bike I've had that I could put most of both feet down, was my YZ80, back when I was 5'6''. I've seen lots of shorter people ride bigger bikes, you'll figure something out that works for you. I find it easier to start my bike by holding it slighty sideways and kicking, or standing on a 2x4 or some kind of block. After a little while, you'll probably look back and laugh at your concern. Happy hunting!