Thanks for the good ideas.
I am definitely thinking about staying in/near Bangkok now and travelling on the weekends to do the climbing. You made some compelling arguments on staying in the capital.
The recommendation for Vina del Mar. I've done some research now and it looks like a lovely place.
My good news of the week is that I found a place for us to live in Madagascar! it's not been easy. We'll be staying on the west side in a town called Mahajanga. Can't wait!