Whoah. I need to check this site more often, what incredible work. I must admit I wasn't thinking of much beyond just some generic things added to the already-existing template of the pub, but this looks totally new. Awesome stuff.
I agree that taking Tweek's fine work and slapping a different logo and color scheme on it would cheapen it greatly (you taking notes, Cyan?). Best to come up with something totally original for future Pubs. I am, as always, open to suggestions on that front.
It seems like it would be best to consult the other Guilds as to what sort of things they would like for their pubs.
At the moment, I'd suggest the Guild of Maintainers should somewhat resemble Gahreesen... lots of stone walls and sharp angles. Maybe some old Maintainer suit models, if that's at all possible. The Guild of Greeters is green... maybe throw in some potted plants and trees to set it off? And something to make it more accessible, so that they can actually welcome people. Maybe pictures of the different Ages in there somehow. Guild of Cartographers could have a map-style floor, with more wooden and earthen tones, and sketch pages on tables around the room.
...I get the feeling I'm forgetting a guild, but I (obviously) can't think of it right now.
EDIT: Wow, that's embarrassing. The Guild I'm forgetting is, of course, Doobes' own Guild of Messengers. That... is hugely awkward. Sorry, man. You should ask around your guild to see what things people think would be beneficial, but just from a decorative standpoint, the Messenger's pub could have a lot of bookcases with scrolls on them. Some of the alcoves could be marked with the GoM different venues--Facebook, Twitter, etc. (though that could run into legal problems, and would look too modern for D'ni.) Perhaps you might want another imager, that can be updated instead of simply added to, so you can have an ongoing "calendar of events" or something.