If the multiverse were real:
-The first book of the Railway Series is instead about "the old not necessarily being wiser". Gordon is the kind one who gets bullied by Edward and other loaned engines for being "new fangled nonsense", especially after Gordon gets stuck on the hill. Meanwhile, Henry shows the worst of the new engines and is eventually sent away after he stops in the tunnel. Gordon eventually proves himself when a loaned engine breaks down and Gordon helps Edward take the train on. Edward goes on to forever respect Gordon.
-The second book of the Railway Series is about contentment. Instead of Thomas getting his branchline at the end, he learns to enjoy his place in the yard, seeing the bright side of it. When offered the new line, he instead suggests giving it to James to make him feel better after his accident.
-The third book is about James proving himself again after his accident and getting his branchline.
-The fourth book is about James instead, showing more adventures on the branchline.
-The fifth book would be about Percy being purchased and showing a "bad influence" for Thomas. Eventually, Edward and Gordon put Percy in his place.
-The sixth book features Henry coming back, now rebuilt to a well-performing 4-6-0 design which goes to his smokebox. The book shows him being humbled and eventually coming back. James even gives him back his number 3, while James becomes the number 6.
-The seventh book is about Henrietta recovering from the closure of her old line and Toby being scrapped. Over the course of the book, she grows to accept that Toby is gone. Percy is also transferred to Ffarquhar to be Henrietta's new engine.
-The eighth book is about Gordon gaining the respect of everyone else, especially Henry, after pulling the royal train.
-The ninth book is about Edward worrying he isn't worth anything anymore, only for him to prove his worth.
-The tenth book is about "nothing lasts forever", and all four engines end up in a museum.