And just more creatures in general. Examples:Ritualist 6 6|61 : Destroy one of your creatures.Particle 2 5|1Particle gains -1|0 every turnJust some simple mid-sized attackers.Aether also needs a permanent of some sort.
I voted for Life and Light.Life, obviously, because it's awesome and needs more love.Light, because I feel that it's currently one of (if not, THE) weakest elements in the game at the moment. It could most certainly use some buffing up.
Aether and Darkness are the obvious choices, because they all have less cards than the other elements.