Ideal location for both Biennale areas. 15min slow walk to St. Mark's square. Nice cheap bars on the Main Street 1mins walk away from the apartment and a supermarket there too.
You won't need to use the vaporetto (water bus) unless you are visiting the other islands Murano etc. as you can walk to the Rialto in 30mins even with getting a little lost.
Quite dark but the apartment grew on us, it was clean and comfy. We ate in for a few meals and the cooker was easy to use.
Very warm so you'll need to use the fans.