I own an 8x but my neighbor has a 920 and I?m constantly tinkering with it, most of your question seems to be about WP in general so I?ll give it a go?
First of all you should realize that looking through forums on the internet, you?re bound to find a skewed opinions, the minority with problems tend to be the loudest in forums, someone with a perfectly fine 920 is going to post about how perfectly fine it is.
Anyways:
1. Speed Fluidity, DEFF better than Android! On par with iPhone, no matter what I throw at my phone, it never falters,
2. I completely agree with you with not wanting to spend a lot of time customizing and rooting etc...I actually love how easy customization is on WP8! And when it comes to email, messaging, pictures, etc? it just works which is awesome!
3. Keyboard very subjective, I much prefer it to android, never tried iphones, but iphones are known for being pretty ****ty at guessing words?again compared to android I remember being really impressed with their keyboard especially coming from android
4. My neighbor who takes A LOT of notes (school, work life) absolutely loves OneNote, and its synced with skydrive which is really nice
5. Calendar is probably the only core application that Windows is lacking in?im sure there?s an app that can replace it, but I don?t use it a lot and haven?t gotten around to it
6. I?ve My neighbor has had a few reboots (less than 5), I?ve only had 1 and it was either right after or right before Portico
7. 920?s camera is superb, haven?t heard about fuzziness or glitchyness at all, most people have had no problems with their camera, and I?ve seen comparison between iPhone 5, SIII, and 920, all have negligible differences in daylight, nighttime, 920 obviously wins
8. Nokia HERE is honestly the second best thing to Google Maps, each one has there forte but they?ll both get you from point A to point B.
9. VERY good SMS experience, I love being able to facebook chat in SMS style
Oh battery life probable wont be as good as an iPhone, pretty sure SIII isnt either, but it'll last your through the whole day with moderate use
Again, app might be a deal breaker, and if you?re paying full price for the phone, make sure your comfortable with possible not having your favorite apps for a while