Everyone wants to type the perfect message or to mess up with people by changing entirely the content of a past message, right ?
... Right ?
Well at least I know I do, thus I suggest the following feature:
Having Discord Nitro permits adds, when you right click on a own message, the option Edit Message Secretly, which leaves no (edited) besides your newly edited message.
It may seem as small as useless, but I'd find it pretty neat.