THere is a really great Elephant Sanctuary in Lusaka, Zambia! We visited there and it was awesome.
I really want to visit the maldives as well. But the price doesn't encourage me much! I need to make more writing on Medium first! ha!
Oh, also, there are great Yoga reatreats at Lake Atitlan in Guatemala. I would highly recommend Guatemala over Costa Rica. We spent over 4 months in both places. Costa Rica is the Hawaii of Central America and Guatemala is the Peru. There is so much culture there, it is amazing and the Mayans are lovely people!
Unfortunately westernization has ruined Costa Rica, at least in my opnion.
Have fun!