The unfortunate result of the current reward structure of pvp in ESO is that it rewards one alliance dominating over the others.
This is reflected in the end of campaign gold rewards as well as the pvp buff system which carries over into pve.
Players that want to maintain the pvp (scroll/emperor) buffs pick the path of least resistance by Home campaigning where their alliance has a very strong advantage.
This creates imbalanced campaigns where one side is much stronger than the others.
Zenimax doesn't seem to understand the the population doesn't really "self-police" themselves. Instead the population follows, like the zerg, the reward path. It isn't as rewarding to be in a balanced campaign.
The reward and incentive system (game-wide and not just pvp) needs a real revamp.
One of the first ways to fix this is to remove the population meters. People have less ability to "flock" when they don't know where to flock to. Also there's a natural disinclination to "join the losing side". This might help (in a small way) by encouraging people to simply play and not to just "join the zerg".