Honestly, i think that what we saw was at most the very beginning of Michael's evolution. In terms of being anticlimatic, maybe it's more a personal opinion. To me it would be great if he fell from the sky like a meteor to help when Alice is about to be killed.
But you know, agree to disagree.
It really seems like a message to the audience. But at the same time Michael is not talking to the player, he is talking to Power.
In that sense him saying "We'll meet again. And next time, you won't even recognize the warrior I've become" is a message to Power, the second apostle.
In that dialogue Michael is telling Power that, despite not evolving the way he wanted (either because of the circunstances or because he failed some requirement), he is still determined to become the strongest warrior.
So there is a reason in game for his words that can be interpreted in a different way.