I like OS2. I like that there are fewer crown clicks required to get from a third party app back to the watch face. I was very annoyed that it took 3 clicks before. I don't like that many of the clock faces that involve photos only have the time and possibly the date. There should be at least 1 or 2 complications so I can add data that is viewable at a glance without touching my watch. While I like Astronomy, Motion, Photo, Photo slideshow (sp?) and animated wallpaper, I don't use them because I want more than just the date and time on the watch face of a smart watch. I mean if Mickey can display my next appointment and the outside temperature, surely ALL watchfaces can do it.
For me the update was painful and while I've already covered this in another thread I can mention here that it took over 3 hours, caused me to cut short on one of my practice runs, and almost made me late for a meeting. In fact the watch finally finished rebooting as I walked in the door to my meeting which means I was wearing a mere decoration on my wrist as I drove to the meeting.
I also have mixed feelings about iOS9. I like the new low power mode. I like the possibility of wifi calling though it appears At&t (and possibly the FCC) have flubbed the rollout. What I don't like is having to reset my phone to get audio during a call and constant loss of bluetooth to my headsets (2 different ones). I don't like instability with apps crashing almost daily. In iOS9, I like the lowercase/capital keyboard. This was one of the few things I liked about Android and I was glad to see iOS finally pick this up. Why am I discussing iOS 9 in a WOS2 thread? Because AFAIK you need iOS9 to get WOS2 and I've gone so far as to warn several friends to hold off on iOS9 due to my mixed experience with it.
I don't have any third party apps yet (that I know of) but I'm sure they are coming soon. Overall I like my Apple Watch and I like OS2.