Pretty simple, have a command that is somewhat similar to what /myadmin oldtags used to be, where you can change what color a rank will have.
For example: /setcustomrankcolor (or probably something shorter) Exec 9 and then Executives would show up as &9 instead of &c.
I was also thinking of maybe changing what the rank's name could be, but I feel like this could be used for abuse, but I will put screenshots of it being used here, and it can be up to (if this is approved) Ryan or Steven to add the option to change rank names for you.
Obviously, this will not change in tab, because tab uses /teams, but it would change this in /list, /o (if you're an admin) etc. I thought of this idea because I use the really old adminchat format from the TFM 4.3 days, and I thought it would be cool if I could make Admin also look somewhat nostalgic.