Aloft can be told to remember name, class, level, etc of players you come across. So if your high level character has come across someone and remembered his info, then it's possible Aloft may (I have not tested this) display their level instead of a skull.
I had an idea for addon that would broadcast mouseovered opposite faction playerlevels in hidden channel to others.
Other people using the same addon get the level and store it in DB.
After that when they come across the same player they can see the level.
But don't think anyone would use it or be interested about it so... Nah...