Weird that you describe the Velo as long, unless you're referring to the strap?
Sizewise, City < Velo or Part Time (both are of similar sizes) < Work.
If you're afraid that a PT is too small, then I doubt the Work would be too big. PT and Work are almost the same in terms of base area; the only difference is that a Work is a bit taller.
You can check out this thread for some ideas of how big the bags are:
http://forum.purseblog.com/balencia...ze-comparison-thread-641103.html#post17124797
Great thanks!! yes i do mean strap size as beng to long! i think ill be choosing between city and part time