Tracking threat on vuhdo frames

I've been using vuhdo for a while now and it has been overall a nice customizable addon, but one thing that has started bothering me is the aggro.
I know there are "aggro indicators" like outlined frame, or a red dot, but I don't find that satisfying out of two reasons. First one being DKs color (since I use class color as HP) being barely noticeable about the indicators which are red lines/dot. And second, I can't see who's high on threat so I can give him salvation.
So I was wondering if there's some way to make the frame glow or get highlighted, change the color slightly in relation to their threat.