your system is two heavily weighted for the more senior members and if a rookie gets on the wrong side of one of you senior members, that senior member can intimidate them, and some are intimidated more than others.
when jillian gave me a neg, i actually thought it was a good thing and that the minus sign was just a computer program deal. i wasn't paying attention to points or whatever. when i found out, i was a bit intimidated, but just briefly. i had come from a far more brutal board (AOL unmonitored). on AOL you can have up to seven screen names and some people would switch to all seven, a time consuming process just to do your eqivalent of a neg rep, and they did it to intimidate people..
people like to be liked. i do. on the other board though, one woman was neg repped way beyond even the number of posters on the board and she took it pretty hard. she was my worst enemy but i ended up defending her because what was happening wasn't fair at all. i told her what was going on and to not let it get to her.
all i am saying is that you neg rep some rookie and all you are really doing is silencing them, or making them leave, or making them angry enough to indulge in petty little fight.
if your community becomes stagnant, it will die. this board is complicated as is, let alone having the more senior members throw their weight around in counter-productive ways.
also, most of you people, you senior people, are very pleasant and welcoming, almost all o you, but the bad one always sticks out, at least for most people. that's just the way it is. i don't think you need that.