These are all treasures. I know them from before but now we have good links and I feel restored!
I think that with the Fuji XE-1, they will be even better in the future as the files even surpass the 5D Mark III at ISO 6400, in the preview tests. So I'll wager you'll be able to do better than even with your Leica when photographing such wonderful scenes in the worse light!
Magically, you can use Leica lenses and have the best of both worlds! I'm not jealous, but proud of your wisdom in the practical decision to add the new Fuji camera to your toolset. considering the cost of travel to these far flung places, the extra expense here is sort of "budget dust"!
Asher