I think that the outcome predicted is more or less right, but that the analysis is very poor. I would take particular exception with the criticism of Carnera's quality of opposition. It is hard to find anybody around worth fighting at the time, who he did not fight at some point. He even fought the guys who all the other contenders of the era were avoiding. He was very far from being a manufactured fighter. Having said that, I would expect Lewis to defeat him, and very convincingly. It probably wouldn't be a first round blowout like predicted. Carnera would likely fight defensively, and nobody was ever able to dispose of him quite that easily, and in any event Lewis might not go for the kill in the first round.
That fight was arranged, and Schmeling cancelled. No blame for Carnera there. While Ramage was a very fine fighter, he would not have been seen as a major omission on your resume, at the time. Hamas is a fair call, but he was on top after Carnera had lost a couple of key fights, so he was probably more focused on other fighters. Probably neither of them wanted it. Carnera did in fact fight Lasky! Not a huge omission I would suggest. Risko was on a bit of a losing streak when Carnera was on the way up. The most likely answer, is that this fight just didn't make sense for either party. All in all, you have rather made my case for me! Nothing very compelling to hold against him!