if you wish to bring back lost players or catch new, the dlc should be more convincing but that kind of games are made for a very niche audience (we are a special kind of elite ^^),

Anyway
I am hoping for new DLC at the end of March/early April. Three months sounds about right.
I wouldn't mind 8 animal dlc with 4 South American and 4 Australian animals. Not many animals would need new rigs
(Koalas and Kangaroos on top of my mind, also tailed SA monkeys if they mean to implement them).