This is one of my biggest wishes. A stadium upgrade feature is essential. If I want to start a dynasty with a team like Idaho, I want to have the option to make their stadium bigger. If I take them to prominence, they should not be playing in a 16,000 capacity dome.
I just wish there was an editor... They did not get Washington's gold end-zones into the game this year and that's kind of a big bummer for me.
This one is a pretty big deal, IMO.