If you have the time and the facility you can always think of dropping by the beautiful,quaint,romantic and scenic island of Burano situated in close proximity to the city. It is definitely worth the additional time on the quick vaporetta (about 30 minutes by ferry). You will like the boat ride in all probability. It is in fact a play of colors that you get to see in this island. You can think of having a meal at the Trattoria da Romano or a pizza at Ai Tre Ponti.There are also hued houses and pretty little canals. Nice place to take a short walk.
There are charming little shops on the way side where you can find interesting masks you can take back as souvenirs. There is a nice lace museum here. You can check out that too. Proceed to treat your senses!