I disagree with several of these additions, baring the ability to turn them off. the last thing I want is random text displaying "So and So" is online or a bunch of chimes while I'm healing in a PvP battle. If anything like that was ever implemented, I'd want the ability to turn it off, which, since i'm lazy, translates into the ability not to use it.
I do, however, want to see an Accept button for friends lists. I've seen people abuse friends lists in the past, and I've actually been stalked in this game once. Only adendum is I think anyone in your guild or alliance should not have this restriction. Though why they'd need you in their friends list and the guild is a /shrug to me.
For the "Player New001 has left the guild" issue: I don't understand why people are asking for this. They left. They don't want to play with you. if they didn't leave, it would have said "Player New001 was kicked on 1-01-0X by Guild Leader Stinky Cheesesteak Breath".
/lfg over a players name in town= /signed. I think a party window is overkill and would become too complex.
General features that every online RPG has that this one lacks
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I'd like you to list every online RPG please. Runescape does not have a party help system, so your not correct on every RPG.