Depending on what interests you, you can arrange your itinerary to end in either Venice or Milan. Lately, flights out of Milan have been substantially cheaper, if you're looking for a tie-breaker. Remember that the train from Venice to Milan is under 3 hours, so you can easily head to Venice for the bulk of your sightseeing, then to Milan the day before your flight (be relatively near the airport the night before your flight home, to avoid stress that morning).
I have particularly enjoyed Ferrara and Padova, which are right on the Florence to Venice train line. and Ravenna, which is a very worthwhile detour from that direct line. Going towards Milan, I liked Parma, and I also liked Cremona, Varenna on Lake Como (north of Milan), and Bergamo (east of Milan towards Venice). I am one of the few who did not like Bologna (although it makes a good base for daytrips to Ferrara, Parma, Modena, and Ravenna) and did not like Bellagio on Lake Como.
I'm not sure I would describe these places as "quaint" - they're a bit too big for that. But one thing they all have in common (except Varenna and Bellagio) is that locals far outnumber tourists. By the way, that's also true of Milan itself; it's a huge city, but not at all dominated by tourism. On my first trip, I remember joking that after Venice and Florence, in Milan it was nice to meet Italians for a change. You need not restrict yourself to small villages to have a "time with the locals" experience.