I'd like to suggest an addition to guild ships (no an amenity though, just a standard feature) that has probably been suggested before:
A guild billboard.
This way, you can leave messages for people on the ship. Things like "Looking for x item", or "Organizing Elite Shroud at x date and time)" instead of hoping that enough guild members are online when you are. Anyone on the ship can read the board, but only guild members and officers can post on it. Maybe set posts to expire after x days unless deleted by the person who put the message up, and give officers the option to "sticky" a post, so it doesnt' expire.