I love that we get to fight and speak with Cray before Apothus reaches him, but I would still love to get that 2nd encounter in the Eastern Barren under the green star, where he would be at least part corrupted.
Additionally, it would be cool, that if the player defeated him twice, Apothus wouldn't take him to be Nyx host, and instead, the player would get to have a encounter with a Lost Cray, and then take him to the Golden Bastion prison.
From there, I imagine he could either be purified by Luca and Torgor, by of course, weakening him in battle. Or the player can corrupt him further +strenghten the bond with him, by feeding him more corruption and dominating him more.
If the player were to be kicked out of the Golden Bastion, then Cray would eventually break out, and find your camp to stay by the player's side.
Just think it would be nice.