Steven Casey, Buffalo Mayor Byron Brown's closest adviser, and the city's first deputy mayor is leaving the public sector to serve as chief executive officer for the company proposing a massive, mixed-used West Seneca development. Casey has left Buffalo City Hall and has joined developer Scott Congel's S&R Co. of West Seneca LLC team. S&R wants to develop a $700 million project on the former Seneca Mall site that will be anchored by high-end retail, hotels and other commercial developments. Congel…
