A thought occurs suddenly. Now I don't know if this would have made its Mega form look better or worse than it does, but now I'm thinking of it it probably would have been appropriate for it to have one fluffy angel wing and one gnarly looking bat wing.
I get the idea here is that Absol is normally mistrusted, and when it goes mega it's basically showing to everyone its true colors. But base, vanilla Absol already had angelic and demonic aspects to it. That was the point—it is frightening and off-putting with its grim reaper scythe face and perchant for disaster, but at the same time it means no one any harm and is a peaceful savior. That's the point of it having a yin-yang head. It's supposed to be both to begin with, a hated sign of ill omen as well as a helpful sign of rescue.
The actual Mega form only softens all Absol's edges and makes it more angelic as though base Absol didn't already have that going on for it. It should have one angel wing and one bat wing to illustrate its theme of dichotomy, and further work upon Absol stylish asymmetry.