I've been to Maldives and Bali before. Out of those two I would recommend Bali. The islands in Maldives are pretty spread out and have fewer nice hotels. In Bali, things are closer together so it is easier to travel around and see different things without having to take boats (like in Maldives).

Basically, Bali is a big island with lots of hotels (but spread across the island) with quite a few things to see. Maldives have lots of islands and you would spend most of your time on one island which is just the hotel and only a few things to do.