While battlefield 4 has several maps, planetside 2 has 4 CONTINENTS.
Planetside 2 has three factions fighting at the same time. Battlefield 4 has only two factions fighting at the same time.
Planetside 2 has jetpacks, shields, overshield, cloaks, and nanites. Battlefield 4 has magical medic packs.
Planetside 2 has a reason for why you can revive dead soldiers, respawn, and heal bullet wounds. That reason is rebirth technology. Battlefield 4 you can revive someone who just got shot to death with a defib, you get healed by magical medic bags that heal you just by being near them, and you redeploy out of thin air or teammates.
Planetside 2 takes place on a terraformed planet that we got stranded on when we went through a wormhole.
Planetside 2 has: tanks with overshields, tanks that float and have afterburners, tanks that have two barrels and can anchor into the ground, atvs that can cloak and have afterburners (also mounted guns), dune buggies that have turbo, air vehicles that can hover then fly away like a jet, flying equivalents of a tank, 12 person transport ship that gives you nanite parachutes, drop pods, and mech soldiers.
Planetside 2 has a much more interesting backstory and history.
Planetside 2 can have 2000 people in the same battle, what does battlefield 4 have, 64.
Planetside 2 is awesome and better than battlefield 4.
The path of the righteous Terran is beset upon all sides by the inequities of the New Conglomerate, and the tyranny of the Vanu Sovereignty. Blessed are they who in the name of Loyalty and Unity, shepherd the weak through the valley of Amerish, for they are truly their brother's keeper, and the finder of lost children. And I will strike down upon thee with great vengeance and furious anger.... Those who attempt to poison and destroy my brothers! And you will know I'm TechPriest Yahuaa when I lay my vengeance upon you.
I can't really judge BF, the only BF game I've played is Battlefied: Play 4 Free, mainly because I'm a CoD person. Of course it's pretty much Pay 4 Free, because you can only play two classes for free... But Planetside 2 is a great game. It has CONTINENT scale maps, not just a boring invisible walls tiny map, but HUGE maps where you can actually travel between the countries, AND it has other continents on top of that. Planetside 2 is also futuristic and has platoons behaving as if this is the real military, strategic planning, not just fast paced action the whole time, but actual strategy, teamwork, group transportation vehicles, JETPACKS, and a huge variety of vehicles. I've never seen this occurring on maps that are atom sized in comparison. Need I say more?