Thunder, Wind, Fire,
In FE9, I usually don't use Ilyana so I don't like thunder (thunder is worse when Soren or Tormod uses it so they don't use it as much), and in FE10 it's worse.
Thunder, Wind, Fire,
In FE9 and FE10, wind is rather useful, same goes for fire. I like the fact that fire deals extra damage to laguz beats since I don't usually have the chance to attack flyers with my mages/ sages.
I vote for... FIRE!!!!