Prefer my idea, TBH. But then I'm not a veteran on here so don't get the acknowledgement that comes with it.
It's not either/or. Your idea and Elwyn's idea are for different purposes. I mean, I actually consider it a simple bug that you cannot target portraits with normal attacks, but can with special ones. That's just silly.
Anyway, there is no obvious connection between a portrait up there and an enemy down here. Which portrait corresponds to the enemy that is about 6 meters northwest from Madora? No way to know, no way to know man. Just cycle through all the portraits to find out.
And conversely, if I just want to attack the enemy with the low health, I'd need to cycle through all the enemies on the battlefield to find out who it is. Or I could just hover on the portrait to find out.
So, they have different uses in my opinion. It should be simple and possible to attack enemies using both methods.