With a travel of about 2 weeks at a time I would do eastern Panama as one and Costa Rica as another (or maybe 2). Costa Rica is the place I have been so far that gave the highest number of species in one trip, and I still missed a few iconic ones.
For the greatest variety over all, Australia must be part of your list because it is so different from most of the other places. It would be a shame going there for only two weeks though.
Niels
For the greatest variety over all, Australia must be part of your list because it is so different from most of the other places. It would be a shame going there for only two weeks though.
Niels