Andrew,
Just curious, why 12' vs the standard 14'? 14' would still be easy enough to handle, and there would not be that much draft difference. Are you thinking of shortening, or scaling it down?
As mentioned, most Cacklers built here have been 14' or stretched towards 16' . My son and I are wrapping up a 15'11" build (state Marine Police are supposed to inspect and issue the HID tomorrow), so I'll be adding an update on that project soon. We built it on 12.75" stations and increased offsets by 12.75/12, so it was increased to scale. Looking forward to getting it in the water and seeing what it does.
On a random note, 14-16' Cackler build uses about the same amount of ply; just a lot less is left on the shop floor. Might be hard to save ply on a 12" build.
Let us know what you decide.
v/r
Bill