You aren't wrong but I think the criticism going Edmontons way is overblown.
First, the Oilers are being criticized for their average age. According to left wing lock
NHL Team Biometrics: Average Age, Height, and Weight | leftwinglock.com , the Oilers are the second oldest team in the league at 30.6. However, like you pointed this number is skewed by guys like Derek Ryan (37) and Corey Perry (39). If you substitute those two with Matt Savoie (20) and Raphael Lavoie (23) it would bring down the total age by 33 years. The average would go from 30.6 down to 28.77. Just changing a few fringe players would take us from one of the oldest teams down to like the 22nd oldest team.
Second, the Oilers are still one of the fastest teams in the league even with the changes that were made. Oilersnation did an article with NHL edge data that I would recommend. It showed that we will still be one of the fastest teams. Obviously losing McLeod, Foegele and Holloway hurts the team speed but it's overblown. Arvidsson is pretty fast and will replace the speed lost by Foegele. Podkolzin will be slower than Holloway but playing 4th line minutes and Holloway didnt play a whole lot in the regular season anyways. McLeod was fast but he didn't really do a whole lot with it. By comparison Skinner is slow but he's quick with his edges. I definitely recommend looking at how unique he is from his figure skating. So yeah we're a little bit slower but Skinner excels at finishing which was one of the Oilers biggest problems last year.
Finally, as far as the defence goes we didn't have Broberg the entire season. He was essentially a 7D during the regular season. He also struggled under both Woodcroft and Knoblauch. My point is that we didn't really lose anything from last year from Broberg leaving, we just didn't gain what he could have become this year. The rest of the defence is Ceci and Desharnais out with Emberson and Stetcher in. Sure it's the Oilers biggest hole but it's not significantly worse than what we had last year.
In the end, our team will be better with Knoblauch behind the bench to start. Goaltending will be better than last season without Campbell. Skinner has more confidence going into this year. We've upgraded our top 6 with a 6 time 30 goal scorer and a 5 time 20 goal scorer. Were gonna have Henrique for an entire season anchoring an important 3rd line with Brown who is finally healthy. We can also afford to rest Kane and have him at 100%, which will be massive. The only question is when and how do we upgrade that RHD which was already an issue last year.