Is Georgia, Nepal, Japan, Bolivia, or Madagascar a better travel destination for two weeks in the fall this year?

My friends and I are planning a 2-week trip for end of September / early October. We're looking for something a little more off-the-beaten-path. We've all been to 40+ countries and been to Europe enough for 10 lifetimes. We'd like to go somewhere a little less traveled with some wonderful geography / nature.

I've come up with a short list of some ideas, but I'd like to get everyone's input on which location would be the best. My ideas are:

1. Turkey & Georgia: thinking see some stuff in central/east Turkey, then go hiking in Georgia

2. Nepal / Bhutan: Either one or the other or both. See some cool culture and hiking.

3. Japan / Korea: One of the other or both. See some cool geography with beautiful fall colors.

4. Chile & Bolivia: Northern Chile (Atacama desert) and then some hiking and the salt flats in Bolivia.

5. Madagascar

My one friend pretty quickly chose Madagascar, and while it was on my list, after doing some brief research, it kind of seems like there's not much there. I know there's some amazing wildlife, but in terms of geography, there's some nice beaches and then one road with the iconic trees. However, nothing really struck me as really insane geography. While I love the idea of going to a country that not many people go to, I just don't know what to do for 2 weeks there.

Anyways, I'd really loves everyone's input. And if there's any other suggestions, I'm all ears.