good, sounds promising
hope you are not putting first aid, signals and covert ops xp in the mix though, or ppl will keep 'whoring' again... if I were you I wouldn't put them in the score, not even reduced by a factor, otherwise ppl would still be tempted to round up their scores that way.
But I think that was already agreed, reading last posts. Only engineering and battle sense, right?
edit:
so, which method will you use? the 4xp per kill -4xp per death one? I think that is the best because the last formula I've put can give funny results if deaths are too few, not to mention divisions by 0