Mine are more about current Apple technologies that making my apple watch less useful:

• Siri is just plain dumb- in 2023, it is still easier to do things manually than to get Siri to do most things (the few features I use in carplay seem ok). I know Apple’s working hard on making Siri competitive with GPT and other such machine learning systems, so this one may come true. I want to use my watch to control everything with my voice, conversationally, wherever I am
• A Walkie Talkie where I can successfully invite my wife… the invites go to some apple pocket universe, even homekit has some bizarro issue with her Apple account and nothing I’ve tried has made any difference.
• Truly User-Customizable watch faces… I don’t want to have to install a third party app or learn watch OS development (which I could do, but come on!) to make a cool watch face on a whim… a set of templates and the ability to embed images and video, can’t be that hard to create for dev teams of Apple’s caliber? A watch, is in its very nature, a fashion item- don’t hold back self-expression for the sake of “creative control”, Apple.