1) Make it open-air - A hundred retainers in a poorly ventilated room, clustered together like cattle doesn't make it attractive.
2) In the open-zone, have as many stands available as the number of retainers allowed in the zone - People will now know exactly how many retainers are supported per ward.
-> SE will also be able to control retainer placement to better alleviate retainer display issues.
3) Make stands free - As it is, no one uses it anymore anyway.
4) Additional NPCs that walk up and down and talks to retainers - Adds life