Personally, for rock crawling, I don't see any problem with the 1.6/16 - It's gotten me all over the place. I'm running a 90:1 overall gearing ratio, and that's got a lot to do with it.
That's:
1st gear - 3.652:1
Low Range - 4.24:1
Diffs - 5.83:1
Multiply them together to get your total gear ratio - just over 90:1.