there is no rule on killing people while healing I've ever heard of... I kill healers as much as I possibly can. I hope eventually they will see there is no point in running in a DM game, and it is best to just finish a fight and heal after everyone is dead, if you need to. you don't get any better at the game by running away and healing.
edit: I don't know if this has already been mentioned, but a detailed stats page would be nice. ULK has run a few servers for mtavc, I believe we had one for vcmp 0.1, and we almost always had a stats page that listed people with the highest scores, and also kept track of weapons usage. you could see how many kills a person had made with each weapon, we also had a random quote from each person. I don't remember how many people it kept track of, it was the top 50 or 100 maybe