As long as your bunnies are outdoors all year, they will grow a nice thick winter coat to cope with the cold. I agree with your sentiment about the price of hutch huggers!
My lops are in a wendy house with a run attached; there is a hutch in the wendy house just to make a cosy area - I just put extra straw and hay in so they have somewhere to snuggle into.
My nethies are in a double hutch and run. I bought a sheet of perspex from B&Q and I just slide it over the mesh parts of the hutch. It just reduces the amount of draught (doesn't eliminate it totally but stops the harshest cold winds) and stops driving rain from getting into the hutch. Again I totally fill one area up with lovely soft barley straw that they can snuggle into. Before I had the perspex I just tacked a piece of plastic over the front with drawing pins and that kept the rain out too.
I think the most important thing is to keep it clean and dry; dampness is a real problem to their health so as long as you clean it regularly and give lots o cosy bedding, they should be fine.