My wife and I previously had a pleasurable stay at Ca' Pisani, and decided to return. We weren't disappointed. It's a stylish art deco hotel with amply sized rooms and, best of all, a superb staff: need advice on a good restaurant and a reservation--done; need a reservation and tickets to the Scrovegni Chapel in Padua--done; need instructions to one or another obscure Venetian precinct--done.
In the morning, we'd wander down to the restaurant, read the International Herald Tribune, and enjoy a nice, light breakfast before heading out. But we also looked forward to coming back to Ca' in the mid-afternoon to drop things off, take a steam bath, and rest before heading out refreshed to explore Venice further.
Venice in February is a treat. The crowds are infinitely thinner and while it can be damp and chilly, that makes it all the more mysterious and magical. Venice will never disappoint you, and this is a hotel that doesn't disappoint you either.