Thanks for all the advice! Sounds like I'm on the right track then, but good to know about getting in there quick with the availability, hopefully there should still be something left, as others have pointed out, were not massively fussed where we land to as long as its in the vicinity (and hopefully its worth a couple of days there too).
We did even think about a while in Japan then down to more traditional honeymoon destinations but actually its a pretty long flight down and could work out pretty expensive.