Required:
Electric Start
Optional:
Reverse - Heavier unit - harder it is to pull it
Multi-speed - Saves having to hold the unit back when doing heavy/deep
Light - Much easier when doing night work
Chute rotational control - convience
Pretty much totally disagree.
Electric start-if an option I wouldn't buy it. Any modern snowblower will have the low compression start, it's super easy to start. My previous snowblower (30 yo) would wear you out after three pulls or so, it's replacement is a breeze. I use the electric start maybe once a year to test it.
Reverse: absolutely required on any sizeable blower. I know from experience.
Multi-speed: To me this is required. I go different speeds depending on the snowfall, one inch of powder is a lot different than six inches of slush or three feet of snow.
Light: would be a nice convenience if I had one, but then again it takes away the excuse about not having to get up in the middle of the night to do a preliminary cleaning. I'll go with lazy over convenience.
chute rotational control: I can't imagine having a snowblower without this, unless you are talking about a lightweight snowthrower for a once in a year snowfall down south somewhere.
Additional required: my snowblower has toggles on each handle to disconnect the drive wheel on that side. This is fantastic, much like power steering. That, plus a working reverse gear makes snowblowing more like walking around than working.
Final additional requirement: one of those plastic pokers to clear out chute jams. Spend the five or ten bucks for one, far too many people lose fingers each year to this. Oh, and have some extra shear bolts on hand as well, if you don't you'll need one for sure.
I currently have a two stage 27" inch Craftsman two or three years back for $600-$800 and it's perfectly fine for a 300 foot New England driveway, even when we had the 36" storm.