Barrie may be overpaid, but this doesn’t help Edmonton

This addresses neither EDM's cap issue nor does it upgrade their team in any way. Easy pass. Build something around Barrie+ for Edmundson and maybe there's a trade to be made.

I like Armia's two way game for the Oilers and Barrie helps Montreal's D but the Oilers already have the same style player in Puljujarvi on RW and he can move up in the lineup. Armia has become an expensive bottom six player.

If Slaf is good enough, he can play with the Habs and one those overpriced wingers you mentioned should be waived to the AHL. No takers for a trade.
But I think Slaf should start in Laval, getting used to North American ice, style of play and really just to settle in Montreal.