This kind of thing has been requested before.
Way back when I created a simple demo addon as a proof of concept for drawing graphs. I can't find the original post, but this thread has a link to source code for my demo graph addon and has a (very) short discussion about how it works.
Anyway, If anyone is interested in implementing a Recount like thing, this may be of use.
Just looked at it, it's what I had in mind when I wrote "Hard to do, depending on graph type"
IMO the bigger problem ist that the events
COMBATMETER_DAMAGE and
COMBATMETER_HEAL are only triggered for members of your own group. If you're interested in pets (like Chiron), it's only triggered for your own pet. One could work around this issue with a HateList-like approach (sending updates in a hidden chat channel), but then you'll have a big overhead filtering out duplicates and buffering up (max 255 characters per message IIRC, and like max 1 message per second over extended periods of time). Even with good compression and only posting your own updates I think it will be hard to keep everybody updated in a timely manner.
There are some additions that CAN be done to the current scrutinizer, but most of them won't be new information (one could filter overheal, but that's about it). One could try to correlate aggro and damage dealt, but that will be error prone and laggy at best. One could add graphs, and with Peryls snippet someone might do that
Recount would be nice to have, but I don't see a good way of getting more than a prettier scrutinizer
PS: I attached my overheal filter for scrutinizer, just install it like any other addon (it hast to be loaded after scrutinizer, so please don't rename the folder

)