So to summarize the whole thread thus far for newcomers.
First download
this mod, it allows you to edit Fallout's INI files without hunting them down, set resolutions, change FOV, the works.
Next you're going to need to make a couple changes to INI files. To fix the Power Armor HUD follow the directions found
here. Then if you're at a resolution taller than 1080 change bComputeShaderDeferredTiledLighting=1 to 0 in your Fallout4Pref.ini to avoid a weird shadow box on 80% of the screen.
For ultra widescreen resolutions you'll want to download
Ci7rus' interface file and Replace \Fallout 4\Data\Fallout4 - Interface.ba2 with his version.
Last you'll want to install
Daisuke's Widescreen Fix.
Once you've done all of this the interface shouldn't be overtly broken and you can enjoy Fallout at 21:9. Wish Bethesda had done all this work for us, but I'm glad it's working.