unfortunately the ledge space has been a hard sell for many years. without street frontage it will never fly. It may be turned into a staff lounge for my staff and the hotel staff.
I'm not sure if you are at all zoned for this at all, but you know what the city could use? A space with daily, weekly and monthly desk rental, a business centre. Nothing (expensive) fancy like Regus. Just a place with wireless, a photocopier/printer, and washrooms, and private or semi-private cubicles/desks. And reasonable hours of access, like M-F 6am to 5pm, less on weekends.