I don't understand the value in either of these deals

What part of Kevin Shattenkirk not wanting to play in Canada don't you understand? Shattenkirk trending down. Howden 3rd liner Pionk bottom pairing D man. Yeah that's not getting you Trouba. And Jacob Trouba wants to be among the highest paid Dmen in the league. Fat chance of him signing for $7.5 million per. He'll want Hedman money or higher guarantee you that. He'll get far more in free agency then he will doing a sign and trade that's for sure.

1) When tf were there ever reports about Shattenkirk not wanting to play in Canada???
2) Shattenkirk is still a good player and only has 2 years left and plenty left in the tank. Is he the same guy he was in St. Louis? No but it's not like he's fallen off a cliff like Marc Staal and at 3.325 per year that is a steal for a guy like him. Howden has middle 6 upside, can play there immediately and take the role that Kevin Hayes was supposed to play when he was traded there. Pionk is a 2nd pair offensive-defenseman who can run the PP or be a staple on the 2nd powerplay behind Buff. Jets likely won't sign Tyler Myers. They have more important players in Laine, Copp, and Connor to sign so a young guy like Howden (still no entry level contract and can step right in) and Pionk (who likely will get a bridge contract no higher than 3M) will significantly help with their cap situation.
3) Trouba won't be the highest paid Dman in the league. He's 1 year away from UFA and simply does not want to play in Canada (maybe who you were confusing Shattenkirk with). Additionally Hedman makes 7.85 and Trouba is not Hedman. Lastly on this front, I used Evolving Wild's contract projections (link below) as a basis for my contracts here so that Trouba contract isn't too far off base.

If you're referring the the Strome and Namestnikov deals I'll explain further here.
Strome: Chicago wants to pair the Ryan with his brother Dylan who were the 2 hottest players after their respective trades in the league to see if they can develop some chemistry. However, as a team that missed the playoffs last year they don't want to give up draft picks in the top few rounds so the Rangers swap picks with them in round 2 so they keep a 2nd, just move back in the round to acquire Strome.
Namestnikov: Rangers are looking to shed some salary as they plan on being big players in the UFA market so they trade back in the 2nd round to incentivize COL to take Namestnikov without having to retain salary.
Trouba: Jets likely do not re-sign Tyler Myers as they have more important free agents to sign (Laine, Copp, Connor) and Trouba has already made it clear over the past few negotiations he does not want to be there. With this trade they get 2 defensemen who's contracts will be on the shorter term so they aren't in a cap crunch again in a few years and combine to make less than it would cost to re-sign either Trouba or Myers. Howden is cost controlled and young, can play on the 3rd line as opposed to Adam Lowry who is currently the 3rd line center and making close to 3M per year. Hell if you want to include Lowry in the trade to clear up more cap space go for it and have him on the 4th line for the Rangers, or rotating on the 3rd with Andersson if he struggles.

I understand why the teams would take the players. What I don't understand is why you devalued your own players. You can get about a 2nd for Namestnikov or Strome on the open market. But you've chosen to send a 2nd of your own in both of those deals just to move up a few spots which is frankly negligible value. And you don't need to send Shattenkirk at all to have approximately appropriate value in the Trouba deal...