There is a different way to figure wingloading so that, no matter the difference in size, a comparison can be made, but I forget the formula. I have been flying for some time and I have come to the conclusion that, for aerobatics:
a 60 size aircraft should have a 16-17 oz loading
90 size, a 18-20
120 size, 21-22
50cc size, 23-26
100cc size, 26-30 and
150cc size, a 30-36 ounce loading.
This is just personal preference. There are people out there flying bricks, like some of the 1.60 size planes with DA 50's in them, at a 30 ounce wingloading and they like them just fine, but for me, I can tell just by watching a plane fly if it has too high a wingloading for my liking.