I don't have the statistics to back any of this up, but I'll bet that, overall, there have been more rate-downs than rate-ups since the karma system was implemented (well, maybe if we filter out the OOT CJ fad back then).
It's actually exactly the opposite if you factor out all the spammers and sockpuppets that have been nuked into oblivion. For just general users, the overall average is an upward trend. Certanly that is not distributed evenly. Some people get far more rates than others in certain directions. People who are generally @#%^s get more downrates except in the asylum. People who are generally nice and make an effort at it get more uprates. We generally act on karma camping in the downward direction. You'll find that unless ratebots are involved, we usually don't act on upward direction karma camping until it gets to extreme levels.
There are people that agree that removing the karma system entirely, or at least the rate down portion is the way to go. I am not one of those people. The more vocal ones on the system tend to be the people who percieve themselves as having been "wronged" by it in the past. Very rarely do those people take an honest look their past posting history and acknowledge that they might indeed be part of the problem.
Regarding the rog issue. We've ben over this, and henceforth in this thread I'm ignoring it. But when it came to karma, it was working exactly as intended with him. He was essentially an @#%^ with occasional bouts of good informational posting. He pissed alot more people off than he tended to help. and his karma trended downwards because of it. When people get rated huge volumes, us admins tend to get curious and check out their rating and post histories. We'll intervene if its just isolated karma camping, but if a majority of a forum is rating someone one way, who am I to stop them? Any further rog related enquiries in this thread will be ignored and or nuked. if you want to read my position on the matter further, I've written probably several dozen long posts on all facets of the issue that should be pretty easy to find.
Regarding the "100-200 posts" pre appended rating number, my thoughts are this. 1. Scholar is supposed to be the normal karma state. Sages and Gurus should be the exception. and 2. the current 16 post buffer, or 32 rates, is far to easy to shift dramatically one way or the other. By making it a higher number , it would tend to take 30 to 40 rates to shift the karma up or down appriciably, as apposed to the 5-10 it takes now. Sufficiently distasteful posters would get there in a hurry, or be reported. But the average clueless noob would get an average of 50 or so posts to figure things out, as opposed to the 15-20 they get now.
Maybe karma needs some sort of "time in grade" automatic promotion factor. We don't have signup dates for the earliest accounts so that would be problematic to implement, but maybe some sort of permanent .10 karma boost for each year of active forum account status. I definitly would not ever consider anything postcount based. too much encourgement to spam.