This may sound like a weird request but stick with me.
I want to be able to associate my characters with some kind of common name (and not all characters to the same common name, necessarily) so that people will know that when I'm in chat as them, it's me. Associating with a common name should be totally optional, and I should be able to have a number of different common names.
I picture that common name as showing up below my character name in the channel user list (but not in the chat log), visually distinct from my character name and greyed or faded so that it isn't emphasized more than my character name.
As one example, this could be achieved by a writer profile that is associated with my characters via a character list, where the common name would be the writer profile's name.
Buy why? I have a number of characters, and usually feel pressured to stick to just one or two so as to minimise confusion and maximize my friends' ability to recognise me when I want to be recognised. Switching characters is confusing and leads to a lot of people greeting me as if I'm new, and a lot of "hi it's me I'm on a new profile" to them one by one as I meet them. If I had a common name, it will be easier for people to keep track of me, and I would be freed up to use many profiles across chats without confusing anyone or suddenly becoming a stranger. Instead, they'll recognise my common name and go "oh, it's just my friend, they switched character." Having to keep track of only one, maybe two names is going to be far easier than keeping track of six or seven or more characters!
Some people have just taken to exclusively using OOC author profiles in chat. I feel as though this experience has some part to play in that, and if those individuals felt it was necessary to stick to OOC profiles, I feel as though that has come at a cost of potential immersion and diversity and character in our channels.