Well, I have started using WP since 8.0 and ya I agree what differentiates WP from rest is its UI, aesthetics, which u mentioned above.
Windows Phone was something daring new, not like Andorid and iOS, picking up something running since Symbian and S series OS days. It was fresh and something new. But new is not always welcomed. (Actually we are also resisting same in some case =) ) People coming from Android and iOS, don't come prepared with learning new, so they tend to find something similar (and if happens some complain they have copied from iOS/Andorid). Well they try new, but many don't like. This is what has brought Windows Phone to this stage.
I guess the beauty and aesthetics , its diminishing in fusion of Windows Phone and Windows 8. I wished they followed some Windows Phone aesthetics in Windows 8 and retained in WP.
Ya new status bar is kind of ugly. But I guess it was to accommodate new action centre. Ya but they could have hide the rest of icons on status bar, which was case in other WP8. But again it may defeat the purpose of showing notification icon, which showed you have got notification. Although some other way out may be there.
Many may argue, Live tiles are there for notification, but at a time it can only one notification, which was inconvenience, for some. Although tapping on icon and seeing all is option, but Android and iOS has made us bit lazy =D
Facebook integration was good and unique, but was confusing for many and lacked many FB features. Many people even don't know they don't need a messenger, it comes inbuilt, although lacking some capabilities of FB messenger. (Fabricating same features in messaging and people app may would have helped). And inhouse app is really a mess.
Music+Videos app was breeze now it is a mess. Its even a mess on WIN8. We are no where getting any Xbox Entertainment advantages being in India.
To sum up, ya now companies are learning to adapt from each other, so soon we may loose the unique tag and will have Windows Phone with Andorid and iOS flavour
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Somes goes for iOS and Android.
In all MS must continue to provide stable, fluid and lag free Windows experience and maintain the Nokia quality on its devices to keep people hooked.