I visited this area independently in spring 2018, and then returned several times in the summer of 2018 on an expedition ship
Madagascar is a great wildlife destination. It is very good value. There are many national parks, and very good local guides. There is not as much infrastructure as in equivalent tropical areas in Asia or the Americas; no highways, no shopping malls, no McDonalds. It is difficult to get around, as the roads are few and small and it seems to take ages to get anywhere. But most of the animals and plant species you will see will be endemics; that is, they are found nowhere else on Earth.
There are many great places in Madagascar to explore, including the remote and diverse Masoala National Park.