I have absolutely no clue why Heinola wasn't paired up with Schmidt more. The pairing did really well together, it balanced our lineup (other than our garbage 2nd pairing that Lowry refused to split up), and it sounds like they had good chemistry away from games too.
It was the end of the season before he got to that point. Heinola had the unfortunate circumstance of starting the season with Beaulieu, which I am sure rattled him. Then Pionk, when Samberg went down, Kovacevic when De Melo was out with covid.
I think the best the Jets had on defense was
Morrissey-De Melo
Dillon-Schmidt
Samberg-Pionk
which was balanced right, but it was short lived once Samberg went down for months. Should that have been the opening day lineup? I'd say probably, Beaulieu became expendable once Maurice was gone, but Stanley had a good season to build of off. Once Samberg was lost the Jets never did find their chemsistry on defense.
I liked giving Heinola a proper development year. The big issue in the lineup in taking Dillon out is the PK, and Heinola got some reps this year (on the Moose). Without Dillon you probably go Morrissey-De Melo, Samberg-Pionk, and then Heinola and Schmidt fill in on the PK. But do you want to burn out Morrissey and risk losing him to injury, when his skating is one of the biggest assets this team has 5 on 5? I had no problem with giving Stanley a chance to have an impact last year. He didn't have a good impact, but that was also on Schmidt, who may be a good talker, but left some things desired on the ice, other than a noticeable good first pass. Which is also Heinola's biggest attribute.
Personally I would give Heinola a shot in,a different defensive formation:
Morrissey-Pionk (two best together)
Samberg-Schmidt (trained together)
Stanley/Heinola-De Melo
That's the spot I want Heinola to win to start his career, because De Melo as a shot suppressor, which I am not sure Schmidt is, is an opportunity for Ville to move the puck forward, and the less the kid has to cover the front of the net the better off we are, until he at least learns some tricks from Morrissey, or De Melo...