Not exactly an all new original idea, but I think it would be awesome if they opened up the doors by the speaker and new monarchy rep as the weapons market. You can have booths with Tex Mechaninca, Cassoid, Suros, Häkke, Omolon, Daito and Crux/Lomar vendors offering their goods. It would also be cool if Bungie implemented a system in which the prices of the weapons are determined by popularity with the players: eg. If Tex Mechanica sells 50% of all foundry weapons a certain week, their prices would go up the next week and the foundry with the lowest sales would have the lowest prices. Each foundry could have their own reputation system in which two is gained by buying and using weapons as well as completing bounties for them. After you reach a certain rep level the foundry vendor for that respective foundry would grant you a quest for the foundry's designated exotic weapon. For example: After you reach level 7 with Tex Mechanica, you enter a cutscene the next time you visit the Tower in which their Tower representative rewards you with a lead for materials necessary to build their new shotgun, The Chaperone. This would add a new layer of depth to the foundries and to exotic weapons by introducing you to the weapon and foundry lore through the specific quest.