For the Dubois-trade, I'm squinting towards LA. They can really accelerate their rebuild by acquiring Dubois for one of their young C's +.
Something in the vicinity of Dubois for Vilardi, Kupari and Spence.
Dubois can be molded to a Kopitar-like 1C, by Kopitar. LA will have an immediate great 1-2 punch and could even be a playoff team this year in this division. This will also allow LA to develop Byfield/Turcotte without having the pressure to put them on the team before they're ready. Having that foundation on offense should also help all the other young F's coming up, like Anderson-Dolan, Thomas, Fagemo, Kaliev, Madden. Heck, maybe that can even help them make a player out of Lias Andersson.
For Columbus, getting a hockey-deal, a young C with a high potential, sounds like their #1 priority. Out of the three (!!) top C prospects LA have, Vilardi is the one already in the NHL (and it sure looks like he has a clean bill of health). Personally, I'm picking Vilardi over Kotkaniemi and definitely over Chytil or Studnicka/Beecher, even if the Rangers can easily put together a better over all package. Vilardi isn't currently as good a C as they would like, but I think that will be extremely hard to get unless Bergevin caves and gives up Suzuki. And finally, not sending him to Rangers, Boston or Montreal should be a nice icing on the cake.