This is NHL19 not reality. Marincin isn't good enough to to play regularly. He can kill penalties but he makes more blunders than Gardiner and has no offence to make it okay. Kadri has been fine this year. He seems to go on streaks where he'll score a bunch and then fall off but he creates chances the whole time. He's a fantastic 3C and Nylander is a better playmaker for Matthews. Hainsey on the other hand needs to be dropped to the 3rd pair but moving Gardiner up is the wrong move, him and Zaitsev have been fine. Dermott and Oz are fine on the 3rd pair as well. Until an upgrade for Rielly is acquired just keep it the way it is. If anything switch Dermott and Hainsey.

The enemy of great, is good. The word fine isn't in the vocabulary of a contender.

Zaitsev has fallen off a cliff. 36 points down to 13 and now he's on pace for 5. Hard to imagine they gave him that extension hoping he'd be a shutdown Dman.

Kadri is fine. Marleau is fine. Hyman is fine. The D as a whole is fine. They'll all need to do more if this team is going anywhere come playoff time. The time is now to prepare for it.

The team is great. Top 2 in the entire NHL and depth to scare anyone. No need to tinker unless things turn south. Enjoy the ride.

The team has done nothing and you're already complacent. They're building an NHL version of Golden State, until they win 60+ games, there is work to do. There is always work to do.

Of course but doing too much can have an adverse affect. The first thing to do is get Nylander and Matthews to 100%. Then we can see what can be done to make things better. Right now is not the time to blow up anything. I understand what you are saying and agree completely complacency is death, however, until really big warning signs show, there is no reason to worry and make a bunch of changes at this moment.

Kadri hasn't been good for a year? That's surprising. Leafs just are just going to get six more months (hopefully) out of Hainsey and Gardiner and then they are gone as UFA. Reilly is have a career year. Maybe having Hainsey as is part is prat of the reason.
I kinda agree with you about Nylander going to centre, just not during the season. For cap reasons, IMO, Nylander or Kadri ar traded next year.

Kadri had that 20 game stretch last year where he only had 2 points. Then Marner was moved to his line. This year his scoring rate is down and his defense is gone. He can finish but he doesn't drive a line like Nylander would.

I believe Hainsey is a big part of Rielly's growth but the production is more a product of his more superior surroundings.
They have floated the idea of resigning Gardiner and they really have to if they want to remain at the level they're at. If he and Rielly were to form the top pair and be dominant, not only would they know it worked but also it may convince Jake to sign for more term and less money.

The Detroit game is a good example of warning signs. Andersen allows this team to play loose but if they don't have him, they're not going far as is. With 30 games banked, the next 20 games are the perfect time to try some new things and if they work, the can be perfected down the stretch with good habits formed heading into the playoffs.

The reason that Gardiner and Reilly don't play together is the Leafs need a puck carrying Dman on each pairing. Right now it's the the three LHD, Reilly, Dermot, Gardiner. I know it's subjective but I don't see why Gardiner and Reilly would be dominant at all. It would force Reilly to play his offside whether it certainly is debatable where if he would be as good. And sure would a Marincin/Zaitsev combo would be hemmed in their own end constantly . What else are the Leaf going to say publicly and to Gardiner and his status next year? Of course the are going say they want to resign him. Why do folks believe what a GM says publicly about players contracts? Sure looks cap wise it's 99% sure Gardiner can't be resigned.
Although I am surprised that Zaitev's point total is way down, let's look at some facts. He doesn't play the PP like he did before. One reason Marner's point total is so high is he player the point on PP. Even Reilly is getting a lot more PP time that previous years, replacing some of Gardiner's minutes.
Like your ingenuity. in putting Nylander at centre now, but Leafs need him to be NHL good ASAP as after his long summer. Maybe getting up to speed as winger in best right now. If he been a Leafs when Matthews was injured, he would have had more centre time,, instead more Lindholm, Gauthier ice time.

Zaitsev's point totals are down a lot majorly because he doesn't get any PP time anymore. Last year the Leafs tried to work on his defensive game more to improve his overall play. He still skates well and moves the puck out at 5-on-5 so theres really no need to bash him because its a lot harder to get points at 5-on-5 and no PP time. He'll get more time on the PP if Gardiner isn't back next season or Zaitsev isn't traded to help with the cap

I'm not bashing him. 2 points in 29 games tells the story.
He had a dozen PP points in his first year, yes, but in an attempt to make him a better overall player, which they have tried to do, his offense has completely dried up. He is a player that can drive a pairing and while I thought he and Gardiner may make a good second pairing, they don't.

He can be a lot better and the idea here is that making some changes could bring out the best in the players.

Hainsey is the only D that can't skate with it and he is playing on his off side. It's not uncommon. If neither Rielly or Gardiner can as well without any drop off, experiment over. Or maybe they would form a hell of a good pairing. Wheels and shot versus elite passing and possession.
Maybe it doesn't work, maybe it does. Who is going to play next to Rielly once Hainsey is done or goes down with injury?

I know I am in the minority, in this venue, believing you don't let your second most important Dman walk in his prime and I'm inclined to believe those that know would agree. Taking Hainsey's 3M and moving it up front next year is not how they make their area of weakness any stronger.

Is Marincin that far behind Hainsey? Not likely. His strength is preventing zone entries and Zaitsev's is moving the puck. They're complementary to one another much like Hainsey was to Rielly.