Let's get this back on topic... There are hundreds of threads talking about the best ways to move snow and I realize buckets are at the bottom of the list (just above shovel). I've used rear blades, converted truck plows and buckets (and shovels!). I have not used a blower. But my question is about buckets (this doesn't mean I won't convert the 9 foot plow, that I won't use my rear blade or try my cousins 6 foot blower).
The only recommendation about bucket size has been to not exceed 7 foot width because it will stress the loader arms too much if pressure is applied to the outer edge. That is a very valid concern and based on comments from other threads where people have bent loader arms with a snow pusher (similar concept) I agree, I should stay under 7 foot. In fact 78" would nicely cover my wheels with wiggle room and be wide enough for any of the vehicles at the 8 homes I plow to get in and out (but 84" would be a little better). 78" would probably also be a better option for manuverability.
A point that may have been missed here is that I'm looking for a much deeper / higher bucket, not just wider. My current bucket is 9 cu foot struck capacity and I'd like to have something around 30 cu foot for moving light materials. I didn't mention it before but I'd have other uses for the larger bucket (like moving fire wood) but the plow would sit most the time.
Finally, I don't think a plow will be good for starting at the road and going towards a house with no place to put the snow near the house. Snow has to be blown out of some of the turn arounds or lifted out with a bucket. While I do believe a power v-plow on the loader arms and blower on the back is the best set up - that is big money and doesn't help move firewood.
So right now the question is on buckets. I've narrowed it down to either a 78" or 84" bucket, probably the Tomahawk due to price, weight and the fact that it has the lowest volume of the three (so that it doesn't kill my roll back force as much) while still being much much more volume than the standard bucket. 84" probably better for snow, 78" probably better for my other uses (acually 72" probably best form my other uses but not big enough for snow). Note that a 72" Tomahawk snow bucket still has 2.5X the capacity of my standard 66" bucket so these are much higher volume buckets that I am considering.