I love Mikheyev and Spezza, but Mik may have just had the best year of his career and got paid for it. I don't think he would bring enough value to the Leafs to consider paying anything close to that contract. Spezza was done. He still showed flashes because he used to be an elite player, but at his age he's unlikely to even perform at the same level as the previous year which was barely a 4th line level.
The two guys we could actually use from last year that haven't played yet are still on our roster (Muzzin and Liljegren).
For Muzzin it's a question of whether we get playoff Muzzin or last years regular season Muzzin. Hes definitely trending down and might be part of a cap clearing trade soon (TDL? Next Offseason?), but a 2022 playoff-level Muzzin and the return of Liljegren would help make our team look significantly better in my opinion.
I like them as 7th Dmen, but replacing Holl and Mete with Liljegren and Muzzin would be huge for this club right now.
Having said that, our issue so far has been Matthews/Marner not producing enough based on their expectations/caphit. However, I wouldn't worry about our star players not playing well enough yet because Matthews will get going offensively. If you'd like to bet his goal scoring doesn't significantly improve I'll gladly take that wager!
Take some solace in the fact that our biggest question mark (goaltending) has been good so far (fingers crossed). If that continues, we will easily get a good playoff seed.