What should be added to the product page regarding stock availability, delivery times, and shipping times? Are there any other tips on what to do or not to do?
Hello Digital Spinach thank your for another question.
All what you shared are good ideas, however shipping times I would not do, as they will not care much about this, what consumers care about are delivery times.
What else, here are all the recommendations Google suggests : https://support.google.com/merchants/answer/4752265?hl=en
As to my personal tips, consider adding floating add to cart. A wish list feature. And for drop shipping specifically, don’t copy any text from anyone, including the manufacturer. Have your own original images, text etc.