I am aware that this may not be the highest priority thing right now, but after things have cooled down, this might be a worthwhile improvement to make.

The thing that prompted this to me was that I was going to change my banner on my profile, but there wasn't really any indication of what the proper aspect ratio for that would be. I ended up just picking a wide rectangle, which works well enough, but knowing what aspect ratio to aim for would allow for more precision when making a banner out of a larger image.

Additionally, there does not appear to be any way to change one's own username. I can only assume this is planned to be implemented, given that profiles contain a link to a user's username history.