Val already bends time but I think I'll go with water for her since she is so in touch with her heart.

For Ben I am bending the rules and going with the Manga-verse's idea of creating a construct of city materials (concrete, glass, tarmac) and say he's a city bender or a specialized earth bender if you want to be picky.

Hank would be air for acrobatics, same with Jess.

Quinlan is water, Andrea is fire as is Thalia (though she's specialized with electricity or plasma) and I have no clue about Anton.