As a commuter don't skimp on wheels, plenty strong 32 or 36 hole to take the pounding of northern potholes, err I mean pavement, drivetrain - the highest level you can afford, I'd shoot for 105 or Ultegra and brakes, good stopping power and Kool stop pads. Oh Yeah a seat that's comfy - for you.

I'm working on a similiar project commuter on an old trek 400 reynolds frame and plan to go Ultegra - but my budget is $1K including paint