why do so many people stay fighting in the middle of the map and let the other factions take the sides. all the way up to the warp gate?
Because it's more enjoyable than trying to capture the continent. Capturing the continent is done by avoiding and breaking good fights (ghost caps, zerging) while fighting at the center of the map is a stable source of enjoyment. The gameplay flow needs to be adjusted. When a base is captured there shouldn't be a downtime while the attackers move their vehicles to the next base, the fight should immediately continue without pause with a battle in the field to get to the next base. Capturing territory should also be harder if you are doing (repeated) ghostcaps or outnumbering the defenders to encourage a closer-to-equal fight where one team tries to have a small overpop rather than bring 3 times more players. Creating continuous enjoyable fights should be the goal of every single gameplay element, and even if you are outpopped you should still have some way to both enjoy it and feel useful to the end-goal of the game.
