You can't look at one or two good picks and call it good drafting. You have to look at total yield adjusted for where the team finished in the standings.
In two of three seasons during Benning's drafting tenure the Canucks have been bottom 6 in the league, and what do they have to show for it? Virtanen, Juolevi, Demko, Tryamkin, Boeser, and then some mid to low grade prospects. The total yield should be a lot higher imo, that simply isn't good enough for three years, two of which the team was complete and utter ****. Now I don't think they deserve to be last in the league, but definitely bottom half of the league, which is unfortunate considering this team is in desperate need of a rebuild, and has a president who is preaching the importance of building through the draft.
In 2014, we drafted Virtanen, McCann, and Tryamkin, who have all proven they can play in the NHL. I'm not even mentioning Demko, who everyone seems to love here. I think our draft haul is better there than most teams except for:
Florida, Buffalo, Edmonton, Bennett (top 4)
Toronto, Winnipeg (top 10)
Detroit, St. Louis, Boston (great pick in 1st round)
These 9 teams also have only one notable player in the NHL (albeit all of them are top 6 Fwd and Ekblad), whereas we drafted 3 (2 top 9 Fwds and a top 6 D).
I would conclude that with 2014 draft that we are definitely on par if not better than Nashville (Fiala and Arvidsson). So that makes us 10th/11th in draft haul, without "adjusting for position" as you said. How much would be adjust for the top 4/5 teams, since there was a clear tier (or two good tiers) of players there?
Kinda tough to evaluate 2015 right now, but Boeser seems like he in on pace with some of the greatest to come out of NoDak. We also made the playoffs that year and re-drafts have Boeser going higher in the draft now.
2016 had us pick 5th again, right outside of the top tier of 3 players, despite that we came 3rd last.
I think we have had good drafting and quite a bit of bad luck based on our draft position in lottery and how the eligible player tiers have fallen in the draft.
Now that we have built a better base of younger players, we can afford to trade a few vets on the team at the deadline for picks. It's too bad because I fear the expansion will actually bring down prices at the deadline since these players acquired are more pure rentals since contending teams do not have space to protect them. It could be the opposite effect however if they don't have the eligible players needed to be exposed....