Well since you asked
I don't like that they have removed most of the Theme functions;
- you can't even create a background color
- you can't edit colors
- you can't choose how long to make icon spacing without regedit
- you can't customize taskbar colors (they only have set choices)
Windows 7 was best, 8 removed some, but left enough to be tolerable
I don't like that you can no longer selectively choose which updates you want
- what if in the future they remove a feature I like or use, I won't have any control
- what if their updates screws up my system, it's happened in all other versions
- why not allow updates to be disabled? <---- this really, really bothers me
I don't like that they removed Media Center, (yes I know) blah, blah
Regardless, of pro and con of Media Center, many legacy softwares used the default drivers provided
by Media Center, now they don't function, they could have at least left (or allowed one to install drivers)
you are not even able to play a dvd, without installing 3rd party software (they abandon everything)
Let's talk about Edge, since eventually I think they will remove IE all together
- I don't like that Edge imports bookmarks in reverse order
- I don't like that you can't easily edit bookmarks, it only allows you to delete one-by-one
- I don't like that you can't reset Edge to defaults
- they said it would have extensions, I haven't heard or seen anything about this
Let's talk about tablet mode
- I am unable to snap to either left, or right screens any more
- I much preferred the Metro interface of Windows 8 (but that is a personal issue)
- I also miss being able to go to the left upper corner and displaying my different app
- For me this tablet mode is just stupid and totally useless
DirectX doesn't seem to be functional (I am sure they will correct this at some point and time)
but again, not even 11, 10 or 9c seem to function, I had to search for an old stand alone install for it
this is really not essential unless you are a gamer, so no biggie
I really don't like the tiled menu, and I still don't like that you can't pin items to a menu (again personal issue)
I won't go into the whole vague issue of the free thing, verses licenses (makes my head spin).
These are just some basic issues I have with it, I could go on, you mentioned some (I like the Charm bar, I thought it was brilliant). But, the above are enough to stop me dead in my tracks for upgrading. It may sound frivolous to some, but for me they are major stopping blocks. Good god it just seems, that it isn't even my machine or Operating system any longer, and after the first year, they want me to pay for this?
I have been a Microsoft person my entire life, I have gone through every version since day one (bad and good), but this one leaves me wanting. I am good with my Windows 7 & 8 for the next 10 years. I have never really thought about a Mac or Linux, but I am willing to make a switch now, where as before I wouldn't even consider it.
On the bright side, Microsoft goes crazy every few years, so who knows, they might abandon this and in 10 years we will have an entirely new toy to play with.