WvWvW - Oil pots
“To Rasa Sum – and back again!”
They deal a ton of damage and while an oil pot is in place – you can’t melee the gates or use rams, without instant death and loss of resources.
I have never seen a wall getting knocked out and gates take a good long while for 20 people to bring down, even longer when they’re reinforced, especially with 5-10 defenders on the ramparts.
Currently, you can take on 4-5 times more invaders then there are defenders if they’re manning a stronghold with ease. In some cases, 3 people repairing a reinforced gate can hold back 40 people and 2 rams at bay for good 5 minutes before the supplies run out. That’s more then enough time to summon reinforcements, even with that many attackers. There is no need to improve anything.