What do you have in mind? They did a lot of aesthetic stuff in the last couple of years (painting walls and even the underside of upper north, signage, lighting, etc., plus the dubious “upgrade” to turf).
Short of tearing it down and starting over, there’s a limit to what they can do about some of the problem areas (like the narrow east concourses that are constrained by Techwood Dr., and the “if you touch it you’ll have to comply with ADA” status of the west stands).
There have been surveys in the last year or two about interest in upgrades that, quite frankly, seem focused on everything but the actual experience of watching a football game. I’m a dying breed, obviously, but that’s why I go to the stadium - not to eat, drink, or socialize except ad incidental to watching the game.
JRjr