I think you should try to limit the amount of people in a campaign to 50 a faction.
Quite frankly, Large scale battles as promised are causing more issues for players than spamming any one skill.
-groups of 12
- Whatever AOE CD you want.
1. A faction cannot stack all of it forces in one spot. It would leave too much open.
2. Small man groups could accomplish more than running around a tower.
3. Smarter groups who know when things happen could actually stop a huge push by a faction simply because they cannot afford to have everyone in one spot.
4. No more Zerg surfing. You will actually need to contribute to your group.
I believe its the population on the server causing the issues.