Gyro!
I would suggest a flatbottom for dry running/puddle skipper. Pontoons are faster on the water due to less wetted surface=less friction. Dry ground, however gives a different type of friction. Dry ground friction is based on the weight (similar to on the water), as well as the shape/surface area.
If the boat weighs say, 10 lbs, with one square foot of surface area touching the ground, the engine has to be able to overcome the friction of 10 foot-pounds (1footX10lbs). If the boat weighs 10lbs with 10 square feet of surface area touching the ground, the engine must overcome the friction of only 1foot pound (the tens cancel - the friction is less, per foot, you still have to push 10square feet). it is not really that easy, there will be a diminishing return, where say 100 square feet of surface area is harder to push than 10square feet ( for the same weight), but you get the idea. Basically, less hull means more weight on the parts that do touch. This can make pontoon and other minimal hull craft more difficult to move on land. This is one of the reasons I use relatively wide, flat pontoons on my craft, rather than tall narrow ones(which would be faster on the water). I think of them as a comprmise, some lower friction, some flat surface area so she still acts like an airboat. Sean