darkSpyro

I was trying to minimize the swappers I own, but I did wind up doubling up on a few elements. This means I've got at least one of all the movement types, but I wound up not getting an Air swapper. Should I track one down, and if so, which one? Or can I get by just fine with regular Air Skylanders?

The Dual Element Gates can be opened with a Swap Force Skylander with the matching elements, or two Skylanders whose elements match. If you have an extra controller, then that's fine. If you don't, then you should track one down before they clear the shelves for Trap Team.

If it helps i dont have one Earth Swopper and i am doing just fine . You dont need one but the question is do you want one ?

If you need to be technical about your needs , you can play and pass the game just fine using cores from SSA starter pack .

If you want one, yes,

I would personally go get one.

Free Ranger is loads of fun with all combinations,

Boom Jet was more fun than expected, and if you swap his top half with Spy Rise, OR Rattle Shake, He becomes SUPER op

Though I would have to recommend getting Free Ranger,
Though Boom Jet I believe is more common...

Free Ranger is worth every penny. Great melee attack, stun enemies with secondary attack, fling (even shielded!) enemies around and off cliffs with leg attack. It's also more convenient to just place a swapper on the portal to open dual gates than it is to plug in and use a second controller. I personally really enjoy playing as Stink Ranger; poison and knockback enemies with palm attack, charge shuriken shield, turn on tornado to trap enemies in a poison/lightning/shuriken-filled windstorm.

If you have all the movement types and you don't mind putting on a core to open the few dual element gates that involve air, then hold off. Otherwise I think you will be happy playing with either Boom Jet or Free Ranger.