The way the caps are set up there's basically no trade they can make that's worth it. Other teams have either a ton of cap space or cap dumps they could move without hesitation to get new players. In caps case the biggest cap dump by far is untouchable and JC and Oshie are lifers as well.
That pretty much leaves Mantha and Kuznetsov... who are not broken down players and could easily have a better season on whatever team acquires them than whoever we get for 8th overall. Imagine Kuz + 8OA for DeBrincat and Kuz outscores him next year on a playoff bound Ottawa.
Capitals also have a hodgepodge of players that don't fit together behind Ovechkin-Strome-Wilson which itself is more of an adequate line than a great one. Oshie and Backstrom for their chemistry are just too slow combined at this point to be together plus will likely spend lots of time on IR between the two of them. Milano is a dud with Backstrom. Mantha is also too slow to be with Backstrom and his lumbering style needs a shifty puckhound buzzsaw Bertuzzi/Garland winger to compliment him and a fast incisive C so doesn't fit with Kuznetsov either. If you just try to assemble a jigsaw puzzle out of the pieces on the roster it would have to be something like
Ovechkin Strome Wilson
??? Kuznetsov Oshie
Snively Backstrom ???
Milano Dowd Mantha
Where McMichael would best fit in place of Kuznetsov and Protas would best fit in place of Dowd probably.
Since Mantha and Kuznetsov are the odd men out, I'd move Mantha for someone like Garland from Vancouver and Kuznetsov to Colorado for their 1st and whatever futures. Get Bertuzzi and Orlov/Gavrikov with the resulting cap space and the best they can for Fever
Ovechkin Strome Wilson
Bertuzzi McMichael Oshie
Snively/Frank Backstrom Garland
Milano Protas Dowd
Orlov/Gavrikov Jensen
Alexeyev/Sandin Carlson
Sandin/Alexeyev TVR
The forward lineup becomes much more shifty/aggressively attacking and less passively reliant on plays happening at least, and the defense if healthy is about as solid as it can be with Carlson, Jensen, Sandin all part of it going forward. Get a coach like Brunette or someone who can attack with 4 lines and play good firewagon hockey extracting as much offense as possible from that bottom 6