Columbus is in a weird spot. They have some big name players, some good players, and then almost never overlap. Korpisalo, Jones and Laine are all net negative players, but could in todays NHL still generate a solid return in a trade. The real gems here are Bjorkstrand, Robinson, Gavrikov and Merzlikins.
This years FA class has some pretty damn solid players. With the cap sitting tight, CBJ is in a position to spend more than other teams on a few forwards. Now - they typically won't. One player is probably more reaslistic. But Danault, Statsny and Coleman are all underrated, good players that would improve any team. Other options are Saad, Tatar, Hall, Hyman or anyone who drives play well on a defensively solid Columbus team. Hamilton is the cream of the crop in this years free agency, but I don't think he'll sign in Columbus.
Some names to avoid are Barrie, Hoffman, Palmieri and Krejci (he's not bad, but he's worse and probably more expensive than Stastny).
The suggested trades are just that - suggestions. Most of them can be with another team, for another return. They are ball-parked, rather than fully thought out. Mostly because you and I probably don't agree on player value, or more importantly, the league-approximation of value I've attempted to emulate. I get it, you think your players are worth more.
Regardless, this is a team that'll aim to win games 2-1 rather than 4-2. That higher variance won't have them finish at the top of the league, but a defensively solid team that relies more on 5on5 than special teams can make plenty of noise in the playoffs.