I doubt TNSE uses a term like "re-tool".
They basically have a couple of tracks if they are moving on from a few core players: 1) go "scorched earth" and tank and gamble that they'll get some lottery luck, and rebuild over a 6 or 7 year timeline; 2) try to makes good trades that restructure the roster around a younger core, while adding picks to add talent in the pipeline.
Either way, they need to hit on some top talent in the draft. They were able to build a strong core through the draft without sinking right to the bottom (Scheifele, Trouba, Morrissey, Ehlers, Connor, Hellebuyck, Perfetti). The only lottery bonanza was Laine, and he wasn't a franchise saviour, nor was Dubois. A later pick in 2016 might have actually been more valuable, if they could have acquired a stud D like Sergachev, MacAvoy or Chychrun.
Regardless, I expect them to make some big trades, but try to acquire younger players that might be ready to have a bigger impact, along with picks to give them a few more shots at top-end talent. I'm dreaming of a couple of drafts like the Stars' when they got Hintz, Oettinger and Robertson with late 1st and 2nd round picks.
Putting together a contender is always a dubious proposition, and I'm not sure there are any surefire formulas. You need a good strategy, good scouting (amateur and pro), and a lot of luck.