First, i'm happy to see that the texture of the guild halls has been upgraded. But now my question is what to do with it. It's nice that you can show that you're in a guild but it would be nice if the guild hall had more guild related functions. Here are some suggestions:
Guild archives icon:
Clicking on the icon brings up the guild screen. On this screen you see a sort main page of the guild, with icon, history and own lore, like guild story. This is made by the guild owner. Here could come something like a in-game guild form. Where guildies can post and reply on messages (maybe organising events).
Guild dimplomacy icon:
Clicking on the icon brings up a screen with a list of guild mates. You're able to send a envoy to a guildmates city and be able to visit it with a singel unit named: envoy. There you're able to see and maybe interact with a guildmates city, this should also be an option for a friend (make a building like an embassy a guildhall but for friends, get my meaning). How to interact should be up to you, devs, but i find it important to visit my friends cities, to see what there amazing cities. Btw the interacties could be done the same way as in capital cities where there is a quest mark above an NPC which you can interact with. (hope that you would do something with this, interaction with friends cities)
Guild bank icon:
I don't know if this one is neccesarry, because this one is already included in the current guild screen. This is were the crowns of the guild are stored. Clicking on the icon brings up a transaction list of the guilds crowns.
Guild trade icon:
I don't know if this one is neccesarry either, because this one is also included in the current guild screen. Clicking on the icon brings up a trading screen. On the left you have a list with guild mates and on the right you have a list with your current resources.
That's all i come up with, i'd like to hear your feedback, ideas and suggestions