Several issues with the Microsoft Store:
1. No option to change the language for the game. ( I prefer english)
2. No option to verify integrity of files. ( One patch for FH3 broke the game so I had to completely reinstall it.)
3. Microsoft Store automatically started to download the game in the backround without my permission. I got no notification, nor where I want to download it. It just put it on C, wasting twice as much diskspace, so I got left with 8 GB free diskspace, the game took 120GB.
4. The interface in itself is just a pain to use, but you can create a shortcut which wasn't quite easy to figure out how to do it.
5. Lack of different management options for your game which are a standard on Steam for over a decade now.
I wish they would release it on Steam, but this is Microsoft we are talking about. My complains are only for the PC version. I don't have a Xbox.
As a side note, it took the developer 8 months to fix FH3 on PC.
That's all fair enough, I see you are looking at the MS store in the wrong way, its not Steam and never was meant to be Steam, is much like Origin, UPlay and Battle.net etc.
I am not sure where you are from however English seems to be the default language on all Win10 games where I am from, unfortunately I cannot comment much on that.
My biggest issues with the store is the downloading times, they take forever and can suck up a lot of juice for your internet. However that's a 1 time thing, and my internet sucks.
You need to treat Win10 Store as a closed system, its basically the Xbox on your PC, its not an open gaming app for people to digest games and mod etc. I actually like that idea, id rather play the games the way there meant to be played so I enjoy the closed system style and it also reduces hackers immensely and considering MS house a ton of MP games, its probably all for the better.
I am also more thankful that the game is on PC in the first place, MS didn't have to bring it across, they could be like Nintendo and Sony and force you into buying a console to play the game. I think the benefit for being able to play the console exclusive outweighs the negatives in my opinion. The games so far iv played run great, iv had little to no problems with them on the Win10 Store.