This roster makes more sense if you replace Aston-Reese with someone like Joey Anderson and then signed a spare d-man.

I like Aston-Reese, but 21 man roster is sorta unrealistic

That might get you 30% of the way to Gibson.

Not that close for Gibson.

1st and Nylander i think will be starting point.

The usual silliness for Gibson. Leafs are much better off resigning Campbell, buying out Mrazek....that costs less than 6.4m Gibson, and the Leafs get to keep Sa. ndin and Robertson.
21 man roster and no 7th NHL Dman.
Leafs are worse now and in the future

Term is a good thing when good players (i.e., players you say you want) are involved, not a bad thing. Sandin and a first not only won't get it done, it will just get you started.

As my friend @palhal says, you're much better off just re-signing Campbell for the same 5 years and less money, unless you think that Gibson is better than Campbell, in which case you don't really think that this is even Campbell's value, do you?

I'm not saying Ducks should do the deal either. But if for some reason, the Leafs offered that deal, the Kings would be a position to sign Campbell. But I'm doubting Gibson would ever think of waiving his NTC for the Leafs.
As a have mentioned before, trading for high priced players , and giving up a lot to get them are going to get rarer and rarer trades. With so many teams close to the cap, and lots of UFA looking for a home, teams can sign UFAs and keep their young cap free assets instead of trading for an expensive players and giving up young assets.