Intentionally sliding around on a slippery flat surface doing doughnuts isn't any semblance of a sign of stability. Try doing slalom moves on dry asphalt and see what happens. :) Now consider what would happen if someone cut you off.
3/4T might do better. 1T might be ok. Most folks only have 1/2T's.
To top heavy for my liking. Putting sleds up on a tip trailer is as much as I want for loading. Agree, a 1 ton would be the best option but then again putting that thing on and off and then storing it would be a pain.