Yeah, I'm not big on the word 'karma' myself, but it happens to be what is out there.

I'm not sure about 'x threshold' either. If 'karma' assignment is weighted it wouldn't matter much anyways.

As for colors, what about a bar that increases vertically and has multiple segments? Higher is better and darker? This would give people two things to lock onto, just in case color is not enough.

just my two beans...