Folks,
I've used both jets and props on varying kinds and sizes of boats over the years. I would have to agree with Medic's comments.
One suggestion, though, is a rig we use here in Tejas called a "Flats Boat". A lot of them come with a flat bottom, but with a large tunnel down the center of the hull from bow to stern. The tunnel is open on the bottom.
At the stern, where the tunnel exits, the shaft of the outboard is placed so that the prop is centered on the tunnel. The motor is usually mounted on a hydraulic jack-plate, so that the prop can be raised or lowered as necessary.
These boats will function in spots that only an airboat could go otherwise, but with the motor down, they have all of the power and "steerability" of the conventional prop. Another plus is that the decks are flat, so they leave a lot of working space available.
Just a thought.
Cheers!
Rob Davie