I think the biggest problem I have with Planetside 2 is map design.

[Babyfark McGeez]

The only thing i'm wondering about with the overall map design is why they decided to go with such "square" maps when they knew they had to balance it for 3 (and not 2 or 4) teams.
But there is one mapping detail that annoys me, the spawn rooms. I know attackers need a way to be able to hold the defenders spawning back, but as it is now attackers can simply spawncamp the defenders with tanks, which is seriously lame.
It's part of the overall "very open" design issue with some bases. Being able to spawncamp the enemy with vehicles because their spawnroom is inexplicably some hut outside the actual base is not nice, the underground bases of PS1 provided a more fair balance between attackers and defenders.
Also tieing in there, being able to capture points with vehices / aircrafts is another (mapping related) thing i don't like, because even if you are there to defend it, unlike you have a rocketlauncher and atleast another guy with you it's pointless to even try.

Edit: I just remembered another, rather small, oddity in the map design; In some bases the vehicle terminals have been planted in a way that a complete newbie-mapper would realize it would result in massive teamkilling, especially with the way you're not having control over your vehicle in the first seconds.
The vehicle terminal in "the crown" is exactly the "prefab" room layout i'm talking about. Seriously, that is silly and needs to be fixed.