Yes, Adam cares about his exorcists, not in the sense of being empathetic or anything like that, but because they are his army. Adam becomes explicitly angry when he sees his army being killed by their own weapons with a barrier in front of them. This is a perfectly plausible argument; it makes no sense to disregard it when his frustration is so explicit.
No, I agree that Alastor is inferior to Adam, but I consider him close to him. If the difference were massive, Alastor would have been injured, since the staff didn't stop the entire attack. And most importantly, there is absolutely nothing to indicate that Adam could one-shot Alastor. He only managed to do so against a weakened Alastor, using piercing AP and Hax.
And technically, Adam literally has an automatic Hax against Alastor even without an Angelic Weapon, since angelic power, even without a weapon, is accepted on the wiki as capable of erasing demonic magic, and Adam literally erased Alastor's magic with his Attack (which is accepted on his page), making Alastor's feat even more surprising.