Some really good posts in this thread, until Page 3 when the usual suspects showed up for their daily thread derailment. Anyway, here's my stab at it....
I think patience is the smartest approach. It's essential to draft and develop in this league, it has to happen, and I don't mean just developing obvious elite talents.
They need to develop some "surprise" lower round picks, I swear that every organization has at least a few young players that come out of nowhere to be impact players (2nd rounders and below). Until this happens, the Oilers will never compete for anything meaningful McDavid or not. Supplement that with some bargain bin signings and more Maroon type trades and go from there. Teams don't build foundations with big splash trades and signings, they build that foundation first through internal development and smart signings then they add a big piece once they are close to contention (like the Kings did with Carter, Hawks with Hossa).
This is the problem though. Even though some of us think the patient approach is prudent, there's absolutely no chance in hell that Chia will stay patient, no chance. They are entering McDavid 4th season, after missing the playoffs by a country mile 2 of the first 3 and Chia's job security is starting to become a little perilous or maybe a lot perilous so there's no way that he remains patient folks, not happening IMO.
The thing is that I don't see a move he can make that will markedly improve the team without subtracting a significant asset. An RNH or Klefbom for scoring winger or 2nd pairing PMD for example. That's a lateral move or at best, a slight upgrade depending on the asset coming back or even more possible, the type of deal that becomes regrettable in short order.
The "all in" approach would require a huge loss of assets to bring in one player who may or may not be a fit and these trades are a longshot anyway.
I think the pick is gone for a scoring winger or PMD unless they win one of the lotteries, don't get attached to it. That's the only feasible move I see that can improve the team in the short term. Forget free agency, they don't have the cap space to add a significant player nor should they sign another cap crippling contract.
Either way, I don't know how far they can go with this coaching staff. The issues with them have been discussed to death, they are just as much a problem as the personnel is if not more.