Pretty good, but Hawks dont do Van trade or Colorado trade.

I expect the caps to pay less to dump Mantha than a second

Van would do that. Dermott and Kravstov don't have a future in Van. Chi town could max retain and move Myers at the deadline for more.

Have to assume the Avs accept that.

Hawks would make the Washington and Islander deals. Not sure Washington does. Proper value in the CO trade would be CO 1st for Hawks 2nd and Rangers 2nd. Trade as proposed is skewed in CO's favor. Hawks decline the Vancouver trade. Not enough value there to take on $6m for Myers.

I would think the Hawks would want to help Berard...with some good wingers, instead of acquiring Bailey and Mantha just obtain a few more picks.
For example I would looking at signing UFAs Bunting/Compher or maybe resigning UFA Domi....maybe two of those guy, and as you suggest not acquiring Myers and sign a another short term cheap UFA Dman or two.

I'm not so sure they do.

Maybe if they really target someone and they don't think he'd be there in another 5-10 picks. Sens 2nd this year would be earlier on as well.
Edit: forgot about the more likely event that they trade the pick

If they aren't trading the first-rounder for a player, they should probably do that trade. Hoping the first-rounder is a high one and at least one 2nd rounder a low pick.

It's a really attractive option if they are restocking the shelves.