Ema and Stefano's place is such a unique stay in a wonderful location. You feel as though you are staying inside a boat, which is very fitting for Venice. The location is super convenient to the Arsenale stop, which makes it easy to get to/from the airport or train station. It's also a very short walk to the Biennale and ~10 minute walk to St. Mark's square, which makes it both really convenient to the major sights but also outside of the really heavy touristy areas. There are plenty of cafes, wine bars, shops, and markets within easy walking distance.
The apartment itself is really cozy and well stocked, and has a number of thoughtful touches, including umbrellas and ponchos for rainy days. The one thing to be aware of is that you must walk through the shower and order to reach the toilet, which can be slippery if someone has recently showered. But just be mindful of it and you'll be fine.
Overall this is a great spot!