Personally, I love Mitch Marner as a player and just as much as a person - he seems like a terrific young guy and ever positive. That said, if he and his management group go out and get some team to sign an offer sheet that is greater than $10 mil over five or more years, I'd say let him walk and take the draft picks. As some smart person said recently, before he signed back with San Jose - don't remember who - would the Leafs trade Marner for Erik Karlson and 4 first round draft picks and the answer would be a resounding yes. So, if you let Marner walk, you immediately free up $10 plus million annually to sign other free agents, and quite a few nice ones on the market this year, and you get 4 first round draft picks. Is Marner a really good player, yes - is he Conner McDavid good, hell no - is he expendable, I'd say yes if the price is too high.
Marner had 94 points last year, mostly assists, and mostly on the end of one of Tavares's career high 47 goals. Marner is also very durable and seldom misses time - in fact, I can't remember a time when he missed a game injured. But the Leafs are ready to let 60 plus points walk out the door with Jake Gardner leaving on defense, and their defense is a weak area for them and they're likely to be relying on one or two minor league defensemen moving up next year. They've also got a ton of young forward talent in the minors and no place to play them. They could also trade Kadri's $4.5 mil to free up cap space and not really miss a beat. Lots can be done, just a matter of if the Leafs' management - same ownership as the Raptors - have the balls to make the big, risky move, and move away from what isn't winning and take a chance.
And by the way, since Lou was so enamoured with Zaitsev that he gave him a stupid long term big money deal, maybe you could let him know that he's asked to be traded and maybe Lou should pick him up.