This was my analysis to the Avs' board:
This is a 'win-win' for both teams, his trade makes NYI better by subsequent moves and the return was better than most D men. Whomever on the main board is making Toews out to be superior than he is, well, I'll tell you my unbiased POV. He was one of my favorite Islanders, drafted and developed. Calvin deHaan was deemed expendable by management b/c Toews was next in line. CDH is a better defensive D man, BTW. I've followed Toews' career since Bridgeport.
Toews is a 'rangy,' useful #4 D man, his straight-ahead speed is thoroughbred-like; ask him to challenge MacK. His mobility allows him to cut off plays quickly; thus, his gap control is his best defensive ability. He has a long reach, which enables him to deflect pucks away, stick check on simple plays. On more complex defensive plays, he doesn't have the defensive IQ to perceive and react. His coverage is either lazy or not cognizant of the threat. He is inconsistent in his reads around the net especially. His outlet passes tend to 'look' lazy; instead, he carries the puck up. Further, weak clears, *blind passes (annoying), weak passes, fumbles the puck; creating turnovers. He's big enough to pin guys along the boards, though I've always wanted to see more physicality, as he lost board battles. They look like half-assed pins, but he compensates by using his reach. He made a few egregious turnovers that cost NYI games in the playoffs, however, he's usually solid, yet not spectacular. I think he has more upside in his D game, though it's small. He's an older RFA and has a lot of seasoning already.
That said, he's a redundancy on the Avs' blueline, IMHO. You have Makar, Girard, Mack, and on occasion Johnson moving the puck forward. IMHO, the Avs needed a shutdown, gritty D man like Hamonic, or a better Schenn/Bogosian/Ian Cole. Not another transition D man (Toews) who isn't as good as Makar, Girard et al.
Offensively, when Devon sees open ice, he takes it. Noah Dobson has the same tendency, a quicker, more aggressive Pietrangelo, but raw; that's, in part, why DT was expendable. For example, the opponent will be changing, Toews recognizes and races up the ice to create a play. IMHO, this is his best gift, his awareness to take advantage of open ice and his N-S speed (again, the Avs have that already). Further, he has a sneaky wrister from the point; hard, pretty accurate. He can pick spots 30% *if he has the time. Most often, he's just throwing at the net; if the Avs are in the playoffs he will do the same, with less time and space. That said, give him a lane, with some space, roughly 1 out of 5 he'll score. I've never seen him take a slapper.
Anyway, that's all I got.