A number of members here have done such an exercise, IIRC. A year is a long time to limit oneself to one camera, one lens, and one film, but I think it can be a useful exercise in self-discipline and, as you say, seeing what you can accomplish photographicall using vintage gear.
So if I were to do something like this, I would choose one of the following three combinations:
Leica IIIc, CV Skopar 50/2.5, Tri-X
Leica M2, Canon 50/1.5, Tri-X
Leica M4-2, Minolta Rokkor 40/2.0, Tri-X
I currently use each of those camera/lens combinations, but it would be interesting to drill down and see what I could do using just one combination for an extended period. I choose Tri-X not b/c it's my favorite bw film (I actually prefer Plus-X and TMY) but b/c of its versatility: I can shoot it from 250 to 1200 and get good results.