Snow plowing with a small tractor can be a problem because the tractor doesn't weigh enough to get traction. I bought a TC29D primarily for finish mowing, so I wanted a light weight tractor. I have 4WD and the wide industrial (R4) tires and it works good for grading and using a rear scoop, but when it comes to pushing snow its light weight becomes a problem. Getting traction on snow and ice requires weight. I aired my tires way down, which helped, and ag tires will work better, but if the ground is frozen it takes weight to get the tires to dig in. What concerns me about your situation is that you mentioned you have a steep driveway. My property has a lot of fairly steep hills, but my driveway is fairly level and we don't get a lot of snow here, so my setup works fine for me. But, going up hill in snow and ice is a real problem for my TC29D (with the blade up), mainly because my tires are too wide (narrow tires work better in snow and ice). A TC21 weighs about 900 lbs less that a TC29, so in my humble opinion it would be too light for plowing snow, even going down hill, and then you'd have trouble making it back up the hill again. A TC29 4WD with ag tires and a couple hundred lbs of added weight would probably do ok.