I'm taking a "wait and see" approach to the Murphy question.
Yes, she was taken as an einherjar... for now. But "valkyrie" and Murphy have been linked multiple times in this saga: it was her callsign in
Ghost Story, Dresden refers to her as a valkyrie in his mental narration, and it certainly looked like Gard was trying to recruit her...
I don't think we'll get the answer anytime soon-- probably much closer to the final trilogy, if not during it. But there's been
much more foundation laid for the valkyrie idea than there was for Butters getting a lightsaber, and we know how
that worked out.
It won't disappoint me if Murphy stays an einherjar, but if she shows up as a valkyrie I won't be too surprised either. >shrug< It's up to Jim, and he's not gonna tell us...

Uriel respects and protects free will, so as long as Murphy had her fair choice of afterlives, I doubt he'd object. He doesn't exactly have much room to throw stones since he's got Carmichael and Papa Murphy working for him in some sort of Purgatory-precinct space. As long as Uriel and Odin are working toward the same goals (protecting reality), there isn't any reason for conflict, in my humble opinion.
I do expect Chandler will show up again at some point, but I'm not sure what condition he'll be in. Probably in rough shape, which is a shame, I liked him.