Defenders Advantage

Why should the attackers have the advantage? Bases are built to inherently benefit the defenders. The attackers have to be smarter.
Smart defenders go on offense behind the attackers line and smart attackers go on defense and maintain a battle line.

Thats why SOE might as well put the flag at the spawn point area.

Don't forget that the devs decided a long time ago to shorten sunderer timers to encourage people to spawn on them instead of the spawn rooms. This is partly why they are shorter. It has less to do with right/wrong as much as encouraging people to deploy sunderers.

That's a measure to balance the advantage defenders have.

What advantage?

Knowing where the enemy comes from and being able to sit in the best spots to farm them as they run in.

My favorite spot for example, is the vehicle terminals under the towers from which I can easily pick people off as they run in the tower. I even have higher ground from which I easily put bullets in peoples heads

Taking part in far more defenses than I have attacks, I'm not entirely convinced defenders have much, if any of an distinct advantage, in PS2 as it stands. Once the lattice gets pushed to the servers, that might change with more predictability in attacks, but even then we'd still have to deal with bases that essentially invite the attackers in. There is an advantage to owning the attacked structure, but the affect is minimal currently.

I'm looking forward to the day where an attack is a prolonged endeavor for all but the most dedicated of assaults, but quite a few changes will need to be made to give defenders a real chance at most locations. At least the lattice might funnel in more defenders to begin with, defending being a somewhat unpopular role to undertake it seems.