I have an idea how this whole Enchant Artifact + weapon + Animate Weapon thing could work.
The artifact is a kind of hull or bubble around the weapon, which protects it from influence and magic from outside (not from inside), but magic can go through it from inside, and it´s deformable, so the weapon stays sharp, when it hits the opponent.
If the weapon gets animated, wings grow, and the bubble /hull becomes too small for the weapon , like the skin of a snake, when the snake grows, and it bursts into peaces.
The weapon is now vulnerable.
What happens with Morning Star ? Morning Star is immaterial and doesn´t need the artifact. You can´t even make a hull around it, the weapon would go through the hull and let it burst in the moment the artifact is created.
I don´t think, flying weapon should be changed.
Explain the players, why Divine Glory should become boring, one of the coolest weapons nerfed, and the card text of Flying / Animate weapons more complicated.