I'm commuting on a 2003 Specialized Allez Sport (or whatever they called the very base model that year) and looking to see if it can easily be made more commute-friendly. I have a basic Trek rear rack on it, which has been fine for these five years for strapping on small items or using a rack trunk. Currently I have a handlebar bag zip-tied to it as a sort of ultra-mini pannier. But even with just that little bag, I have occasional heel-strike issues, and now I'd like to get a bigger bag to use for carrying a laptop computer.

I know I can jury rig some extenders to move this rack back a bit, but does anyone have a recommendation for a relatively inexpensive rack that might work better with a compact frame like this?