To go on a different tangent, I want a round Apple Watch. I know it's not the most efficient use of space, but dangit I don't want the weird little (but constantly-growing) square! If I have to have something on my wrist all day, I want it to look nice and not like a brick.
Crazy idea: Just get a regular round watch :-P
Even better idea: Get a Casio FX-91 [1]. You'll get used to its shape pretty quick - like the 100 Million other humans who already have. Good chance it will still be produced 30 years from now, too, so if you lose it or break it you can get a new one. Costs a tenth of an Apple watch.
Try Garmin if you want a round smart watch. They get good reviews and the sporty types who own them swear by them.
Can’t imagine Apple ever doing this, though, because a round display is pretty terrible for displaying the sort of content and UI elements that iPhone/Apple Watch users are used to. Much of the UI and all existing apps would need to be completely redesigned.