Hey Ronan!
These are all lovely interpretations of the respective locations in Avanthal! A bit misinterpreted, though, but still pretty. Honestly, I'm a bit envious of these.
But yeah, going back to my point, the Red Diamond tavern and the Luminary Commons are both large buildings, most especially the latter. These locations are both social hubs, so many Vanthas flock to them for food, drink, and merriment.
The Red Diamond even has a second floor to it. And a lot of tables, and chairs around the fireplace and stuff! Anyway, I just made a sketch of the place. Since it's where my character works, I am familiar with its layout. It pales horribly in comparison to yours, but it will do. Valkyrie, feel free to correct me if there is something wrong with my interpretation!
As I have said, this is just a rough representation, and proportions may be slightly off than what I intended. Moving on, the gray lines is the floor area for the second floor.
And yes, the Luminary Commons is far bigger than the Red Diamond. Imagine all the mess halls that were supposed to be in each and every Holds are instead found here. So everyday, the Winterflame cooks have to cook so much for so many people, that's why their kitchen are really big and have all these cooking stuff for every cooking needs.