I don't think there's any huge disagreement that the max hp for ramps and walls is a bit absurd. I propose decreasing the max on both substantially and having ramparts have a lower cap than walls.
This will help combat turtling/stagnation of the users that have max ramparts and aren't worth the effort to try and kill. Also by having ramparts being lower than walls it creates weak points in barriers and encourages the use of more intricate defenses rather than just surrounding yourself in ramparts. (A rampart is basically the gate in a medieval wall sense, the gate is typically the weakest part of a wall but obviously has the benefit that it's able to be used to pass the wall. Them having the same HP cap doesn't make any sense)