I wouldn't mind Trouba and he certainly would improve the D, but i wouldn't deal Kreider or Buchnevich to get him. If WPG took their 1st back plus Dallas 2nd and DA i would do something like that, though the Rangers would probably need to add Vesey or Namest for salary purposes.
Nothing to be curious about Prod, Trouba has taken a handful of majors in his NHL career while McQuaid has 3 dozen so while the total penalty minutes might be the same, Trouba's penalties lead to PPs for the opponent. With the acquisition of Lemieux McQuaid won't need to fight but he can provide the defensive physical presence the team has lacked for decades. Trouba's offensive talent will cost much more than McQuaid, money the Rangers don't have barring significant roster moves by Gorton.