Your bottom 6 doesn't get you into the playoffs IMO. Lucic and Gagner are huge salary sucks on the bottom 6 too, so I dunno exactly how much you think you're adding there.
I think having actual good 2 way players in the bottom 6 does get them to the playoffs.
An essentially non-existent bottom 6 is why McDavid/Drai had to play so many minutes... and basically got the team nowhere because they barely tread water at evens +3 and +2 respectively for McD and Drai.
You do that each year and that pair will burn out from overwork as they will not want to work their asses off for an 80 pt team that's out of it by Christmas. They'll quickly resign themselves to being an also ran team and their production will drop 10-20% as well because why work your ass off when the team is crap behind you.
A "good" bottom 6.. even an "average" bottom 6 means opposing teams can't just feast on those bottom 2 lines and makes the performances of Drai/McD/Nuge actually matter and they don't get burnt out either playing more than they have to.
I absolutely think having 6 guys in the bottom 6 who can all get an expected ~10 goals plus being solid 2 way players will not only help the top 6 get more space out there... but helps team defence as well.
The bottom 6 is essentially 1/3rd of the team and that aspect of the team is completely broken currently. Absolutely what is needed is a complete overhaul there.. 6 new cheapish bodies that are capable of solid play at both ends of the ice.
Yes you have Gagner and Lucic as well as "anchors"... but those 2 aren't as big of anchors if you had 6 guys in the bottom 6 that were competent... plus you are less prone to injuries as well because there's some decent depth to move around the lineup ... betting the farm on 1 or two bigger name forwards means 1 injury pretty much puts the team where they were last season and even one regression means you haven't really moved the needle forward at all.
Volume of decent players is what's needed in the bottom 6.. rather than 1 or 2 good/great additions.
That's what is separating the Oilers from being a playoff team.. not a Nyquist or Connolly (who individually may realistically not even put up a lot more goals than what Chiasson added last season).