Proximity bonus needs to be completely removed, only give points for damage dealt. Currently an Arbalester will get ~2-3 points for a full HP to zero kill from across the map,, while a shielder can triple those points by doing nothing except RMB in the time it takes the Arb to reload. Shielder classes dominate current score system, so do pikemen.
Defensive, passive playstyle that don't do anything except sit in blobs avoiding damage are the only current winners in this system. I get less points for going on a rampage behind enemy lines winning 1 vs 10s against enemies than a shielder will get doing much less damage but closer to teammates, leeching their points.
It is a neat system but the proximity bonus is simply too good compared to actually doing damage or getting kills.