I have not gone to it too deep but so far what i dont like is
Lock Screen.
I wish it remained as it was on WP8. I used to make wallpapers myself but now they dont "work"
this for example
above the white line on top it would show all connections and that stuff
white box in the middle - time and whatsapp message
and white line at the bottom - lockscreen notifications
now it's not right, doesnt fit, and new pic's wont work ((
Notification Center
where is the icon for data connection ?
more about data settings - why did they remove connection speed (2g, 3g, lte) I have 928 on tmobile and to send sms i need to switch to 2g. Known issue
Keyboard.
Why did they remove the comma (,) I know it's under dot (.) I,also,know,some,people,used,to,type,like,this,hitting,comma,instead,of,space)) but common really
and I dont like the little icons that show up while i type "type [phone] and phone icon show up"
Gallery/ Photo
kind of dont like the ALL section and why are all photo editing apps removed from there. (I know you can open picture and hit edit)
App list
Dont like games being showed there
Lock Screen.
I wish it remained as it was on WP8. I used to make wallpapers myself but now they dont "work"
this for example

above the white line on top it would show all connections and that stuff
white box in the middle - time and whatsapp message
and white line at the bottom - lockscreen notifications
now it's not right, doesnt fit, and new pic's wont work ((
Notification Center
where is the icon for data connection ?
more about data settings - why did they remove connection speed (2g, 3g, lte) I have 928 on tmobile and to send sms i need to switch to 2g. Known issue
Keyboard.
Why did they remove the comma (,) I know it's under dot (.) I,also,know,some,people,used,to,type,like,this,hitting,comma,instead,of,space)) but common really
and I dont like the little icons that show up while i type "type [phone] and phone icon show up"
Gallery/ Photo
kind of dont like the ALL section and why are all photo editing apps removed from there. (I know you can open picture and hit edit)
App list
Dont like games being showed there