I agree, I would like to see some little (or big) changes to the chat and guild information in-game. Nothing huge, but just the things you mentioned would definitely help. Also, while we're at it, some very useful tools for guild owners would be an option to ban and permanently ban players from joining the guild (a blacklist type of thing, where you'd be able to un-ban players as well). Another really cool and useful idea would be for owners to be able to 'sticky' a message where it would stay at the top of the chat to ensure that players will read the important message.
In addition, I think it would also be very useful to have different ranks in a guild. Not just having one owner do everything on his own, sometimes it's difficult to manage a guild at all times and would be extremely beneficial to have something along the lines of a Co-owner. Essentially, the only benefit to these ranks would be giving them (your most trusted guild mate(s)) the ability to kick/ban inactive/disruptive players. As well as the tool to 'sticky' and 'un-sticky' messages.
These are just some very basic and general additions that would help out a ton for guild owners.