Sorry KM I see this as opinion, even if you're purely using CD numbers:
Beams is a rare type of mid as he is both an in and under mid and as you rightly point out is damaging on the outside with his transition footy going forward visually more so than Lyons. Sure mids are not necessarily needed and we'd probably afford some of our fringe mids as trade.
However I could not see Lyons or Hall as a good fit for our team given Beams versatility, we have an Adams that covers Lyons game, and Hall is purely outside giving service I50 we have the likes of Sides, Phillips and Treloar for that and I'd argue Sides and Treloar have more impact than Hall. Sure that's my opinion but I think others would agree there's strong argument for.
On both Lyons and Hall, (against the grain - and I'm surprised it is against the grain honestly having watched a lot of both) but I'd consider them comfortably inside Collingwood's best 22 (or any best 22).
To grab my fully healthy best 22:
My fully healthy best 22:
B: Brayden Maynard Lynden Dunn Tom Langdon
HB: Jeremy Howe Darcy Moore Jack Crisp
CEN: Taylor Adams Scott Pendlebury Steele Sidebottom
HF: Tom Phillips Brody Mihocek Daniel Wells
F: Jordan De Goey Mason Cox Jamie Elliott
FOLL: Brodie Grundy Adam Treloar Dayne Beams
BENCH: Jaidyn Stephenson Brayden Sier Josh Thomas Will Hoskin-Elliott
Lyons and Hall pretty easily come in for Thomas and WHE. I'd only select Howe, Crisp, Adams, Pendlebury, Sidebottom, Phillips, De Goey, Grundy, Trealoar and Beams (unordered) ahead of them. They've both for mine got everyone else comfortably covered at the selection table if I'm picking the squad.
I'd have loved Scully also and have him ahead of the rest. He could displace Wells after Lyons/Hall enter the frame and this team takes quite a large jump. Lyons would be the club's best stoppage player (top five at stoppages in the competition on performance) and Hall the clubs most damaging/impactful offensively (a rare player with his speed as a rare high impact offensively type with that speed but then he finds a rare amount of the footy for someone of his type). Scully when he's right to go would be the elite runner above Phillips/Sidebottom in terms of ground covered, running both ways, has better speed - he is another grossly underrated player and the competitions most elite runner. The only doubt out of those three surrounds Scully given his ankle injury, but if things go to plan he is back playing some time during the second half of the season - and he's a walkup start on any team in the competition as with Lyons/Hall. Or at least they should all be on performance. Scully is more widely accepted as capable, but with Lyons and Hall, as with a lot of players it's about appreciating them for their strengths and what they bring to the table, and they're two on the back of their points of difference who really seperate themselves and put themselves well ahead of many regular senior players. Scully's leadership and professionalism set him apart and make him an asset wherever he's at.
Just adding Lyons/Hall/Scully to the above unit I'd look at something like:
B: Brayden Maynard Lynden Dunn Tom Langdon
HB: Jeremy Howe Darcy Moore Jack Crisp
CEN: Steele Sidebottom Scott Pendlebury Aaron Hall
HF: Dayne Beams Brody Mihocek Tom Scully
F: Jordan De Goey Mason Cox Jamie Elliott
FOLL: Brodie Grundy Jarryd Lyons Adam Treloar
BENCH: Taylor Adams Tom Phillips Jaidyn Stephenson Brayden Sier
As I'm sure is clear. I'm a fan of all three and feel they'll each provide their new clubs with tremendous value and be the three most apparent bargains of this trade period.
In a comparison between Lyons and Beams. Lyons is the better stoppage player/contested ball winner/tackler. He'll win the clearances at a higher clip. All his inside stuff is better. I also like about Lyons that because of how contested his game is, he unlike Beams doesn't just perform well when the team is going well but he'll bring it every week and still go well when it's not going your way. Lyons just doesn't have as complete a game and while capable forward of centre and actually a better kick i50 than Beams (Beams is a stylish looking kick but not the best kick to target) and doesn't have as complete of a game and is not as damaging as Beams around the 50m or i50 which gives Beams value on this team as you can stick him forward and he's still playing good football. There isn't a lot of separation in my view in terms of onfield performance/value between the two. Where Beams separates himself from Lyons and puts himself in front in my view is from a leadership perspective with Beams having led a club, learnt under Hodge for a year, having that premiership experience. So if they cost the same thing - Beams is the guy I pick. At their respective prices in terms of what you'd give up, for mine it's a no brainer Lyons irrespective of list needs is the pick of the two with Beams overpriced and Lyons remarkably to me having no value.
And I don't mean to sound like I'm ragging on Beams. He's a best 40 mid in the game still and in the top 30 mid discussion. He's only behind Sidebottom and roughly in the discussion with Pendlebury/Treloar/Adams in a difficult to separate top end group at this stage of their careers, but Lyons and same goes with Hall has been blatantly disrespected by Gold Coast - each getting dropped at stages and then traded or in Lyon's case cut. I'm as a fan seeing this value very disappointed that Collingwood didn't go after the three. I'd have taken those guys, Jeff Garlett if I could have for another late pick and a Jon Patton for a late pick if GWS were paying most of his salary. All phenomenally underappreciated this offseason and all walk-up starts who make any team better.