The 1648 would be more stable because its 2 feet longer. That means it has much more surface area than the 1448. For a 14 ft boat to be as stable as the 1648 it would have to be a 1472. They don't make those and even if they did, who wants a square boat? People always assume that width is what is responsible for stability. While that is true to some degree it is not the only factor. As an example look at a 10 ft kayak over a 14 or 16 ft fishing or ocean kayak. The longer kayaks are more stable. When looking for a kayak you want a long skinny one. Not a short fat one. Long and skinny cuts through the water good and is stable. A short fat is stable but is like a plow going through the water. Ever seen those dudes in college or in the olympics in those really long rowing boats haulin tail. They look really tippy but but they are actually very stable to thier length. Surface area is where its at when it comes to stability.
With all that being said, a 1448 is a very stable platform. I have even seen them turned into small airboats here in FL. As long as you don't mount the fan too high and deck it low you should be very safe. I think it sounds cool... If it were mine I would....
Pull the seats out, foam the bottom, deck it low so the whole boat was a shooting deck with lights all the way around. Mount a couple seats on removable pedestals so you can pull them out and have the whole boat to work from. Slap a 20 hp tiller with a honda fan right above it. Put my gas tank and Batt up front under a small raised deck with railing and your in business.