Feature request - Adjust tag information

It would be nice if there was an option to choose (on the list box to the right) the columns to display like in the main interface and their order. For example I believe track titles, if they exist, would be better for me and artist on a second column if the album is a compilation. Another thing I'd like to see in a future version would be an easy & fast way to display the changes that will be done if I hit the OK button. For example red text color if there will be a change and green if it stays as it is.