It would also give an incentive for realms to create guilds. A ruler could create the 'Most Noble and Excellent Order of Keplerstan' and a noble awarded a certain rank in that guild could include 'Knight Commander of the Most Noble and Excellent Order of Keplerstan' in their signature.
Equally it would allow the creation of flavour titles to be used in signatures, like 'President of the Keplerian Senate' or 'Royal Historian of the Keplerstani Empire'. So I think a feature like this would get a lot of usage.
