Flyability versus wing loading is an interesting topic. One would initially think that increasing the installed power in linear proportion to weight would do the job, but it doesn't. My calculations indicate that power must be increased far more, in fact, power should be increased to be proportional to the 2.5 power of weight, if flyability is to be kept constant. Ten percent more weight needs roughly 27 percent more power.

Some old Spitfire pilots claimed that the friendliest Spit was the Mark 1, simply because it was so much lighter than later versions. Double the power, and double the weight, makes for an airplane that is much more demanding to fly, mainly because recovering from too-low airspeed takes much longer, and thus produces much more altitude loss before the airplane is happy again.

I would be inclined to use a healthy 1.2 cubic inch, or larger, two-stroke at that weight and wing loading to get a pilot-friendly airplane; a four-stroke of similar capacity would be a reasonable compromise, for those who like four-strokes. Otherwise, it will tend to be an airplane that you fly once in a while, when you feel in the mood for a challenge.