It would be worth having that hole on D to know that your center core is complete, your winger core is pretty much complete, and your goalie core is complete. As JetsAlternate mentioned, there's time to fill a single weakness through drafting, and Tanev only has a few years of overlap anyways. Acquire alot of picks and draft alot of defenseman.
The lack of a 1C and being stuck in that position was the dealbreaker for me.
With every other position solidified, it could be feasible to make do by, at a minimum, only adding two solid top four D-men to support Hutton/Tryamkin over that three years. If you have a 1st line that's a legit 1st line, a 2nd line that's a legit/above average second line, a potential star goaltender, two-thirds of a solid 3rd line, and an existing top 4 pairing, I think that can work.
If Dubois was a surefire centerman, I would agree with JetsAlternate.