See how you have the "Arcane Intellect" bar as a header? Make it so clicking on those headers will toggle showing/hiding of the list for that buff. There are other good ideas posted here for what you could show on the header bar itself (Perhaps switchable between average time left, lowest duration left, etc.) Not sure how you would handle multiple buff type aside from either giving them their own movable header bars or listing them together. Pretty cool looking so far though.