The Hawks will have control (by either having a player signed or by owning their rights) of Keith, Seabrook, Murphy, Gustafsson, Manning, Forsling, Jokiharju, Boqvist, and Mitchell. Maybe another prospect or two too (Krys?).
That'd make our defensive depth like this
Keith Jokiharju
Gustafsson Seabrook
Forsling Murphy
Boqvist Mitchell
Manning
I like Murphy, but trading him for cap space next year when we're loaded with RHD's biting at the opportunity sounds like a smart choice. I dislike Manning and will hope he magically disappears. Thus our defense would look like this
Keith Jokiharju
Gustafsson Seabrook
Forsling Boqvist/Mitchell
Cheap 7th D
Let Boqvist and Mitchell fight for a spot in preseason. Whoever is more ready and capable to play in the NHL gets a spot, the other goes to Rockford for a year. Sign a 7th defensemen for cheap who'll mostly sit (like Davidson).
That would give us Keith, Seabrook, and Gustafsson for highly experienced players, along with 23yo Forsling, 20yo Jokiharju, and either 20yo Mitchell or 19yo Boqvist. And then whoever else for a 7th defensemen.
But that group above is a good mix of old and young. We don't need to have Beaudin, Mitchell, and Boqvist all start in the same season. We can ease them in when they are ready and ice a relatively competent back end throughout that time frame. No need to trade for or sign more help on the back-end.
For forward acquisitions, either someone cheap like a Dzingel who can help with scoring depth, or sign Panarin. Most times when you sign a UFA, their best years are behind them. Panarin might be the exception due in good part to coming over to the NHL so late in his career. He's my main target, but if he doesn't want to return or the cap won't work, signing a lesser name will hurt less financially, especially when in Dzingel's case, they grew up in the Chicagoland area and would find some extra value in that.