Just for the record, I never drink on the job.
This scooped - paddle thing was too good to pass up with violin parts littering the bench and the ever-present duct tape calling to me.
I'd worry about a paddle poured of epoxy and fiber. A facing of Carbon fiber tow on each side would help stiffness and overall strength.
Check out some "vacuum-bagging" setups. they ensure full contact between veneers and fibers when gluing.
Don't plan on bending and gluing 3 or 4 MM plywood as the internal glue lines may not be as strong as the new glue lines you will be making and the 90-degree offset between plies is probably not just what you are after.
I like Mick's idea......carve/sand a form, at least for the face of the blade. Pre-cut ruff's a little bigger all around from your veneers, and use slow epoxy......then, use the vacuum set up or wrap cord around the whole rig after plastic bagging it all.......and wait for it to kick before unwrapping. plan on making 1-2 test blades before getting just what you want.
Piper