I have used WP for some years and as a low to mid end phone os it's perhaps the best (haven't used new android phones in this segment though).
As a non English user I must admit the app gap is HUGE. Perhaps one out ten advertised apps is also for WP ASP also. Streaming on demand (in Denmark) is almost non existent (on video: Netflix works, but lack cromecast, one have an app, but it lags terrible , HBO, viaplay (Scandinavian) , and a few others is only on iOs/android), on streaming audio it's a little better.
Also I feel many commercial apps lacks features comparing to eg android.
Also the lack off using Miracast (not on 1029), mhl and cromecast - not to mention no add word to dictionary in Danish is quite annoying
Here drive is the only app I have found to better compared to a similar app for android. Even office disappointed me with no edit or zoom in power point
and the calendar is only syncing for 90 days - so for business use it have some issues as well.
There is also the locks preventing developers doing great stuff like location based SMS.
So in short I doesn't hate my phone, but I doesn't see my Lumia 1020 being faster than my sgs3 and apps also stops working (especially drive), and it doesn't have any special features besides the brilliant clearBlack screen (some models)...