The first person or party that hit a mob gets all credit for the kill is kinda silly imo. Most mmos outside of classic wow have phased that out for general participation which makes more sense as it promotes helping in the open world and general engagement of the community.
I've seen so many cases where a low level person going to a ce is just running around in a circle being chased by a mob and only one or two people helping or even people dying when I was low lv and couldn't even do anything to draw agro.