I'd highly recommend the Witcher 3 since it's a great game and we can help you out with any issues you run into.
Removing Black Bars from CutscenesDownload either the
2560x1080 or the
3440x1440 exe based on your intention.
Find your Witcher 3 exe (Likely places include C:\Program Files\Steam\steamapps\common and wherever you install GOG games.
Take the exe you downloaded and replace your Witcher 3 exe with it (this is totally reversible but you can copy the original exe somewhere else for safekeeping if you feel better.)
Then in order to fix the UI to make it move to the far corners of the screen see
here.
Moving the UI to the edgesGo to Documents\The Witcher 3
Open the User.settings Folder with notepad.
The seventh line from the top should be uiHorizontalFrameScale=1, change it to uiHorizontalFrameScale=1.3
Save the document
Right Click it and choose properties to open up a little properties window for the document
Check the Read-only box and click ok
3440x1440 is also pretty tough for a gpu (even a 980 Ti) to keep up with. If you find that the game feels choppy I'd recommend knocking the resolution down to 2560x1080 and using that exe for a great looking game with everything running smoothly.
Good luck!