We had a great time a the palazzo in Valletta!
I first stayed a week in a smaller room and the host made the switch to the Jaques Suite very easy. No need to store the bags anywhere in the meantime, just a clever cleaning schedule.
That being said, the room itself is super spacious and the historic building charming. The cleaners are very friendly and attentive. And the host, Jean, is a great guy. If you need any tips, he will know to help you and if anything doesn't go by plan—we had a power cut—he will find a quick and creative solution.
The palazzo itself is located in the city of Valletta which is completely walkable. From there you can take the bus all over the island, or the Ferry to Gozo.
For anyone wanting to explore the islands, the palazzo is heartily reccommended.