I wrote recently about how the Apple Watch does some things very well and how third party apps are somewhat superfluous.
To be a successful smart watch, reliable notifications, excellent battery life and decent information presentation is crucial, but there is one area in which a traditional watch wins every time.
The ability to check the time whenever you want in a millisecond is what a watch does. It is what Android Wear does. It is what some Nokia phones did, but not so the Apple Watch.
Too many times it takes just a little too long for the experience to be seamless and it gets annoying over time. If you have worn a watch forever, it is very noticeable and it is a watch after all. With that should come the ability to tell the time no matter what you are doing and without the need to move your wrist in a specific way.
If Apple can offer a simple always-on display in the next version, the Apple Watch will have gained parity with all other watches in terms of practicality. 2-3 battery life would also help.