Finger independence

one good exercise is playing this chord with both hands: G#BDFG#
and then strike each finger's key while holding the other fingers down.
something like 20 4th finger, 20 5th, 20, 3rd should be good.
after you suceed (without moving the other fingers) you shouild try two fingers at once ( 3rd and 5th, and 2nd and 4th).
and you should at all time hold your hand curved and the fingers slightly bent (normal hand position)

As a pianist, I can say that Hanon helps a lot, just start at a slow tempo on the metronome and slowly speed up. When you get to the quarter note speeds and you're having trouble, try stopping on every beat. It can take a while, and doing a boatload of slow speeds on those things can be a real pain (I know) but it seriously improves your figures. Schmitt is easier and a lot shorter if you are absolutely sick of Hanon and in need of variety. Together they make up the bulk of my technical exercises.

Just practice every day, and remember, sometimes it can take a while to actually see major improvement,

-Landon