I agree with everything you said. I've seen a lot of bad things being said about Sam after the episode so it's nice to see there are other people who think the same way as I do.

We also saw his eyes turn demon-black when he exorcised Samhain, which likely doesn't bode well.

His eyes don't actually turn black. If you look closely you can see it's just the lightning. That's probably done on purpose to keep the viewers guessing did they or did they not turn black. :)