To optimize the model I suggest using the optimize tool in LithUnwrap (I like the one that comes with reality factory 0.76), it took a 500 poly elite arm from halo ce and shrunk it down to about 150 polys

(I can't remember the exact numbers, I did that a few weeks ago).
Why not build a little remote controlled Tank? One the size of an action figure perhaps?
Those handles would be a pain to pep, definately use wooden dowels or toothpicks.
Perhaps I'll try to unfold it (although I'd have to do it in 1 sitting, I only have the unregistered pepakura designer 3,

)
EDIT!!!
I unfolded the scorpion and saved it as a picture, the flaps are not numbered, but if you like a puzzle, here it is:
sorry if it a little confusing :rolleyes
It is approximately 10 inches long.