Your big Cub is flying with different [better] reynolds numbers and I'll bet a different [easier to deal with] wingloading. The only standard rule is that the heavier the plane with respect to it's wing area, the less forgiving it will be. If a small model of a light plane like a Cub has bad tendencies and needs special attention to keep from stalling, it's either lugging around too much onboard equipment, or it's also overbuilt. At the opposite end is a Cub kit out there that is built so light, the airframe is too flimsy and the plane can't stay trimmed. So there is a happy medium for all sizes, they have a target weight range that allows enough strength for the forces of flight and they aren't built so that they "crash well".......which for a lot of overbuilt planes is a self fullfilling prophesy.