One of the biggest complaints Warhammer Online players have about RvR is the static nature of keep siege. Usually, attackers zerg the front door and once inside, zerg the main stairway leading up to the keep lord. This provides a slightly (read: very) annoying chokepoint and little room for strategy. To be fair, Mythic's reasoning for the initial design was that keeps are designed as defensive fortifications. Why wouldn't defenders want to funnel attackers into a single chokepoint? Unfortunately, it isn't very fun from a gameplay perspective.
All that is about to change with the new keep designs coming to WAR in patch 1.3.1. The most significant change is that all keeps are getting a bigger footprint and will feature a second set of stairs leading up to the keep lord.