I don't have personal experience with that hotel, but reviews are excellent.
If that doesn't work out for you, we loved our stay at Palazzo Alfieri: https://www.palazzoalfieri.it/en/index.php
Because we also travelled in off season, we were able to afford an Exclusive Suite with River View. This was like a luxurious mini apartment! There was a large bedroom with a huge bathroom. The shower was large with various types of showerheads and coloured lights. There was a vestibule/entryway. On the other side of that was a mini-kitchenette with a small fridge, microwave, and a counter with stools. Then there was a chaise longe and, behind a pony wall, a jetted tub with a television over it. The hotel had wonderful breakfasts, and the view was lovely. We could even see Ponte Vecchio.