Depends on how the new multi system works. If people's main goal is to literally just win the round by whatever means, then some proximity based XP/gold might be OK. But if its mostly about the score you don't want people finding new ways to leach, without actually taking part in the fights, just standing around trying to survive as long as possible, getting in the way and not really contributing until you absolutely have to.
If its about encouraging team play well the people who genuinely will use team work have the incentive to do so already, the best incentive possible; do whatever is in your power to win the round, whether that means going around in groups, sacrificing yourself, hiding, retreating from impossible fights, whatever is your teams best interests is what's rewarded currently. Going around in blobs can be good, but forcing fights just for the sake of getting a few more points or standing around getting in the way could result from making gold/xp less based on simply winning rounds. I want the game to remain tactical and reward people for simply winning the round, rather than for scoring points that won't ever truly represent someone's worth anyway..you can't predetermine how to allocate points for team work, just not possible. A little reward for being in the vicinity of a kill might be OK though, just needs to be balanced with everything else
