Option to pick Onion skin color and position

It would be really nice if you could add an option to choose the colors for the onion skin and the position(in front of current frame or behind it) as right now it's too hard to see the onion skinning as it(the blue and red tinting is hard to focus on) and as such I can't really use it as much as I would like to. Would be nice to have it set up more like this: where it shows the solid silhouette of the previous frame in green, and the solid silhouette of the next frame in red behind the current frame.