I think players like Connor and Morrissey to start with based on contract status, then you add to that group. I only say "re-tool" because I think people have the idea that a rebuild is only by trading anyone with any value and starting over.
Your timeline estimate seems reasonable to me, and I also suspect that if done in the right way -- i.e., young and competitive players who are willing to buy in and work hard to provide at least entertaining if not winning hockey -- then the fanbase might bear it.
But I don't see this org doing it, especially under Chevy.
They've been half in / half out for years now. We saw it when they brought in plugs on D to add "stability" and "character" instead of promoting from within and easing the way for a future, and we've seen it with such deadline adds as Zach Sanford, Eakin, Benn etc., and the loss of even later-round picks wasted to acquire them. We saw it in the refusal to trade Stats for anything at all when they knew they weren't making the playoffs and that he wasn't resigning, and we saw it in the refusal to retain salary on Wheeler in order to oil the market for a trade.
They aren't resigning PLD. They are unlikely to hang onto Scheifele, and I don't see how they'll convince Helle to resign here for anything less than a gigantic and team-worsening long and pricey deal. I also don't see how they hang onto Heinola, Chisholm or even Stan unless they're willing to shift Pionk or Schmidt or DeMelo or even Dillon, and I don't see them doing those things without absolutely having to.
IMO, they'll try to keep the gang together, because they "believe in this team," still. Unless players make their own decisions and force their way out, I can easily see Chevy running this back for the most part, especially if they make the POs, and then deferring the biggest moves as long as they can, even to keeping PLD as their own rental just in case.
Maybe they'll surprise the bejezzus outta me, and act boldly, decisively and brilliantly to make the proactive and creative changes necessary to ensure a long window of high-level hockey and playoff appearances, plus the odd contender window, but I just don't see the org taking such steps unless forced to.
It's been said, correctly, that this team is often playing not to lose instead of playing to win.
I think of the Jets org similarly -- making moves in the spirit of not losing, as opposed to squeezing every possible margin in order to win.