0
The only problem with smaller, is it's less weight also. My 4x4 Kubota kinda sucks to move snow with because it's so light and ends up spinning. May be different with an actual plow blade that angles, but snow with any depth, you'll still have to pick up and push off to the side with a long run. Also, once you put the bucket down to push the snow, to amount to anything, you'll need the front wheels just about off the ground, then you're back to 2wd again. For me, the ATV pushes the snow better, I can usually get out of anything (except the blizzard last year) using the ATV, then the tractor to widen things up
I have thought about selling mine to buy a bigger, older one. The thing that sucks when purchasing a Kubota, they hold their value, so you pay big for them upfront. Mine is a 2008, and I'd probably have to fall back somewhere in the 90's to afford a larger machine at what I could sell mine for.