Wrote a long review but it got lost in TripAdvisor somewhere. Here's the short version - villa is spacious, beautiful and clean, with plenty of lovely bathrooms and very comfortable beds. Kitchen area has everything you need (including an espresso maker) and the pool is great, although a bit cold at this time of year. The sea is also a little cold, but still possible to swim with a normal swimming costume (we took wetsuits and snorkels, though, which I highly recommend).
We rented a car so I can't comment on the buses, but it's a steep walk to the shops and the nearest ocean access (rock-pools, which the kids loved), and the beach and restaurants are quite far away. But I have 3 kids so I'd rather have a comfortable place to stay and a short drive than a small flat and a short walk.
What else to say? The landlord is outstanding - left us in peace and when we requested a high chair, it was delivered within 90 minutes. On Easter Sunday. There's a great balcony with a barbecue but we didn't use the barbecue so I can't comment much on that. Looked good, though.
All in all, it's an excellent villa and I highly recommend it. Oh, and Mellieha beach is lovely and the town is great and close to all sorts of lovely places.