Except Udawalawe, Yala, Bundala and Lunugamvehera, what are other national parks you are recommending for wildlife safaris?

Wilpattu national park and Minneriya national parks are in the top of the list. Minneriya national park is famous for Elephant Gathering. 
Wilpattu national park is the oldest and largest national park in Sri Lanka. It is widely regarded as the place to spot leopards in its natural habitat. It is also the best possible park to watch the Sloth Bear which is a highly endangered animal in Sri Lanka.