He won't be scoring 15 goals from the 2nd PP unit with very limited TOI at ES.
We've seen time and time again how quickly this type of player falls of a cliff. Post knee surgery Perry is not cracking our top-9, count on it. If you're giving him 16:00 - 16:30 of ice time, which player are you taking TOI away from to give him that? He will not be anywhere near guys like Kapanan and Johnsson in overall effectiveness.
Not to mention he's a RW. Which one of our RW'ers do you honestly see him beating out for a spot? He's got zero experience on LW, so don't even go there.
I'd be more than ok with....
Nylander / Matthews / Kapanen
Hyman / Tavares / Marner
Johnsson / Kadri / Perry
Mikheyev / Gauthier / Moore
Assuming Brown is traded for cap space. Johnsson and Mikheyev move up spot until Hyman is healthy and one of Bracco, Korshkov or Marchment draws in on the 4th line along with Moore and Gauthier.
I see no problem with that group and I think Perry could be a 35 point player on Kadri's wing. Their playstyles matchup really nicely, IMO. Connor Brown had 29 points playing that role last year and he's an offensive black hole at times. If Toronto could get Perry for Brown's money, or cheaper, I'd do it.
Before last year Perry scored 49 points in 71 games for the Ducks. The two years prior to that he had 53 points and and 62 points. If the Leafs medical staff believes they can get him 75% back to his pre knee injury form, he's worth a gamble on the cheap.