I suggest two things:
1. Guild leaders and officers having a different color when they chat in guild chat. Either a different shade of the current color or another color entirely.
2. Allow members to use officer chat by typing /officer, but don't let them read it. This way members can say things to all officers/leaders online at once without having to whisper them individually OR having everyone in the guild read the message. The guild officers can get back to the member via whisper.
I know. I mean that guild officers and leaders should have a different color in guild chat so members know when an officer or guild master is talking.
The chat mechanism could do with a bit more love overall, not just Guilds.
I think a system for tabbing individual chat channels, as well as a way to tab private conversations (whispers) so I don't lose replies in seas of local chat, would be nice.
A separate tab for Market Trades would be excellent too, so I can keep track of trades better.
A way to filter chat channels as well, would be nice. So instead of seeing all channels of chat by default, I could filter out local chat and leave it in it's own tab. And filter out emotes from appearing in my chat window.
This would also be desirable so I didn't have to type '/1' at the start of a sentence if I wanted to talk in Zone Chat.
Even just an exclamation point would be preferable to /1.
This is all pretty standard stuff in other MMOs, having an unintuitive system for communication really only hurts the game instead of helping it, if you ask me.
You can use officer chat.
Just use /o when you are an officer.
Otherwise /o will do a different command.