For commuting i really would consider the Marathon Winter. I’ll probably be using my own soon, but as I said you can test it for a week or two if you want.
“Deep snow” you say? I thought with the green city council, the bike paths were cleared almost before it starts to snow (the sidewalks on the other hand…)
I’ve written a couple of “reviews” on studded 29" tyres:
Schwalbe Ice Spiker Pro 29 x 2.25": Schwalbe Ice Spiker Pro 29 x 2.25"
I wrote that this tyre is good on bare asphalt. It’s not. I probably rode it too short to tell.
Studded tyre: Schwalbe Marathon Winter 29 x 2.0 : Studded tyre: Schwalbe Marathon Winter 29 x 2.0
Don’t worry about the uni. Should I ever need it, I’ll borrow it back for a short time. You’ll probably want to replace it with a better 29’er eventually anyway. When that time comes you are welcome to tell your wife that the new one is mine too. 
I have 125 cranks for the 29’er if you want them.
No complaints about the Nimbus Stadium saddle? It nearly killed Ed Pratt.