The Brawny Edge has great effects in a non-supers game, but other than the additional point of toughness (which could also be purchased by the power which has no statistical requirements), it is difficult to determine what the additional effect of the Edge should be with regard to "load limits." I recommend the following when calculating load limits and max weight for "superhuman figures." Brawny continues to allow character to carry/lift 8/5ths the weight of similar characters.
Thus the Seasoned Colossus in the example below (d12+8 Str) would be able to lift 50 tons without the Brawny Edge and 80 tons with. This puts his character in line with his Marvel counterpart and seems to match the intention of the rules.