Kapowtotheface,
I'm a bit late in response, but it should be said.
If your game is forcing you to use margins in 21:9, you can spread game manually to get rid of them.
For example, Mass Effect 2:
How to spread manually:
http://www.wsgf.org/node/28740Note:
- Those instructions were for Manual PLP. For 21:9, it requires some adjustment, but would work. You would need to adjust numbers in this way: pretend you have a 16:9 center with skinny side-screens. This would produce full-spread game with HUD on your fake "16:9 center".
- Also FWS menu's resolution override was not tested & may work fine (instead of the LUA edits). Again, you would pretend you have PLP in all these numbers.