The problem with WvWvW isn’t the scoring system, the problem is that winners win more. As a strong server captures more and more stuff, it becomes easier for them to steamroll their opponents.
Regardless of what the score is, if one server owns 95% of the map and all they need to do is play whack-a-mole it is depressing and makes me not want to play. Furthermore it also kind of breaks your “bonus” system since shortly after losing teams recapture something it just gets taken back again by overwhelming numbers. In practice, losing teams do not hold onto stuff for very long, only winning teams. I suggest you take your algorithms into question.
Here is how you balance population differences:
Why is it that the WINNING team gets +15% health and 150 all stats from orb bonuses, while the LOSING teams get extra xp / mf / karma from outmanned? All this does is allow the winning teams to pull further ahead, making for steamrolls when we want close games.
My solution is to give players increased damage vs players/gates/guards and reduced damage from players/gates/guards. This bonus should be directly proportional to the current population difference. If your server has 1/5 the players in WvWvW to another, you should be able to fight players 1v5 and have it be a roughly equal fight. If for some crazy reason you are the only person online on your server, you should be able to solo keeps or even stonemist if your opponents don’t make a decent effort to defend.