Yzerman didn't give up a good D prospect (ranked #9 on Detroit's prospect list) for Perlini to turn around and trade him to Pittsburgh for their 3rd round pick in 2021 draft.

With the Helm trade I think it works much better if you do this:

Edmonton gets Helm
and
Detroit gets Gagner and a 4th.

That way Edmonton gets Helm without Detroit having to retain any salary. Since Gagner's contract is up at the end of the season Detroit opens a roster spot a season early and a 4th round pick. I think that works let me know what you think about that.

Regula really nothing more than a depth D, Yzerman was probably just looking to make some changes to a stale roster. There just isn't room next year for Perlini, already no room for Rasmussen and Veleno, and if Perlini comes back Zadina or Svechnikov has no roster spot

Regula had no future with the Wings with Hronek and Seider on that right side. If he makes it to NHL, I don't think he turns into anything more than a depth defenseman who is solid in his own zone. If Perlini doesn't really prove he's worth a roster spot, Yzerman will get rid of him. It was small risk move with decent upside, if it doesn't work out its not a big deal because it was worth the gamble

Your signings are too low, Anthony Mantha will get 8 x 7.5 Tyler Bertuzzi 7 x 5 and Andreas Athanasiou 6 x 5.5 more then likely.