When they add a FaceTime camera I will consider upgrading from the AW3 LTE. Beyond that I’m not sure what else could be improved. I have 0 issues with battery life and I’m a heavy user of LTE daily.
Adding more hardware features doesn't necessarily mean "improvement". There just isn't a good reason to have a camera on a wrist-worn device, no matter how speedy the hardware is or how refined the OS is.
(I also think it'd be a mistake to ask users to pry open the hidden diagnostic port, because that'll open up an ingress point for water, never mind that relevant health monitors which communicate wirelessly are already available now)
It can be made thinner, or with faster processing, or better battery life, or a wholly new charging system, or new battery chemistry, or with faster Wifi/LTE radios (personally I'd like to see a return of an FM radio tuner like the old iPod Nanos had, but those days appear to be gone), or improved optical sensors, etc.
But it's inherently limited in what it can do... or, really, it's limited in what it
should do, because it's still just a wristwatch. It's more powerful, computationally-speaking, than the iPhone 4 was, but I think we can all agree that the AW would be terrible at things that we've been doing for years on the iPhone, like editing movies or playing Grand Theft Auto.
You have to stop thinking of thinking of it like a mini-smartphone and start thinking of it like an extra-strength wristwatch. Cramming smartphone features into it just makes a hard-to-use smartphone. But add features that are appropriate for a wristwatch, and it'll get better. We've never seen optical HR sensors added to the iPhone, right? (well, there's at least one HR app that uses the camera and flashlight, but you can't wear the phone on your arm all day long) That's one example of a hardware feature that's better-suited for a wristwatch than for any other gadget.
