I've been looking everywhere for something like this, but nothing's turning up. I use Pitbull 4 for my raid frames as a healer. Is there any way to get the functionality that Vuhdo has (and I think Grid has a plugin as well) that it calls a "cluster finder"?
Basically, it enables you to configure the raid frames to calculate how many people would benefit from an AoE heal on a given target. It can either display the number as an indicator on every raid member's frame, or highlight the frames of the people who would be hit if you cast the heal on your mouseover target.
Also - is there a way to filter incoming heals by whether or not the person's actually in range of the heal? (For instance, if I start casting Prayer of Healing on a target, I only want to see that incoming healing on the targets who are within 30 yards of the target I'm casting on.) Might not be possible, since I haven't seen that functionality anywhere else, but worth asking.