I like the feature that when a guildmate logs in, the other guildies see the message "guild member so-and-so and logged on (or off)." But It would be a nice touch if it said "guild master" when the person involved is a GM of the guild. That way members learn who the gm's are more easily. It would be a nice way of acknowledging the status of GM's who organize those guilds.
I find it better if people don't know that you're a GM of a guild. Until then, they just treat you like any other guild member. But as soon as they find out, some will put you into a higher honor than before just because you're a GM and you can kick them from the guild if they wrong you. Then there are others who start begging you for a higher rank even though in the end, your rank is just a title. Unless they start kicking people for no reason other than "I did it because I can".