kyselad

This. The biggest issues in my head are tire/fender clearance (for which the WT is far superior) and chainstay length (I don't know if the WT is even better at all in this respect). A bikes with generous geometry and clerances performs a lot better for the purposes you describe, and this is actually one place where conversions of old "sport touring" geometries really shine IMHO, especially on 27"->700c conversions that generate even more clearance at the expense of a bit of bb height (but who cares on a townie?).

Also keep in mind that it's tough to find a low trail bike these days (the VO polyvalent is one notable exception I can think of off the top of my head), so be careful about how much you load up the font end of the bike lest you wreak havoc on your handling.