Now obviously it would never happen, but I thought it was an interesting thought that popped into my mind after waking up 30 minutes ago or so, but how amazing would it be to be able to disguise as other characters rather than other classes? It would serve a pure RP purpose rather than a PK advantage for lower levels, and obviously would mean it resulted more in the complete breakdown of other characters and if it were implemented some checks would obviously need to be made in order to make it more balanced. IE: Halfling Thief couldn't disguise as say a Giant Warrior who's well known and could even be limited to specifically race only instances. When it comes to Undead races, they'd be able to disguise as both Human and other Undead characters though who specifically do not have unique titles. That way it would eliminate the ability to appear like characters who are well known in terms of longevity, and the time limit on it could be made to last no more than a few hours or so, but in that time you could throw so many people off as it would extend to who lists as well for those few hours, but because of how it would affect that as well, I doubt it would be done easily.
So do I expect anything to come of it? No, but it definitely made me think how completely under utilized the skill could truly be if it were made more useful than simply changing professions.