My approach is to buy what I think will be fun to ride and them modify it as necessary for commuting. For the seven years I've commuted on a GSXR-750. I put on some adjustable bars and raised them as far as possible without cutting the fairing (about 1" above stock); I welded up a bracket that bolts in place of the passenger grap handle and mounted a tail trunk (from J.C. Whitney); I mounted mirrors from a Katana (so I can see something beside my elbows). It's an 'interesting' commuter and I've ridden it on some 400mile trips. Now I commute on an Aprilia RS250 - also with tail trunk.