What i've done on my old bike was have a 2 incher on the back and a 1.50 on the front. On new bike i have 1.50 on front and 1.75 on back... it works pretty well and the skinnier rear allows for a 80 psi vs 60 psi max which really helps rolling resistance on regular pavement and when i have stuff on the rack. I have a town/transport/utility bike, not a road bike, so... perhaps you could go to a 1.50 inch, or is that too wide?

- Andy