The out of the way location is a significant challenge when considering other uses for this facility - its location was never great - other than for rail operations. And when compared to other rail stations in large cities, with a few exceptions, this station is far removed from the central business district and further, it is not conveniently located to either Kensington Freeway or Thruway - so not a lot of driveby traffic for retail etc . Real estate and development is all about location - and this location is not good with respect to access and existing amenities, business, drive by traffic, foot traffic and, gulp, light rail service.
So, I think it needs to be unique and have a built in draw - my suggestions are:
Casino complex (nod to Mr. Weaver) -
Condominiums and apartments ( perhaps 150 to 200 at sq. ft. varying from 1,000sq. ft to 3,000 sq. ft.each) in the tower and other large structures, parking in larger structures at grade level and retail and food amenities in the concourse
Creative "Arts Building" - artists living space and work space + local retail
Corporate campus - 500,000 sq. ft. is suitable amount of space for a single corporate entity or a incubator facility ( cheap space for biotech startups, etc.), back of house space for a large New York City bank, back up data center, satellite administrative office for the University of New York etc.
All of these uses may take issue with the active tracks being close to the building (especially the rail connection from the north) - noise, vibration, dust and dirt from trains are problematic - so some thought might be given to mitigating these issues by demolishing the orphaned concourse over tracks and the platforms, realigning the rail connection from the north to increasing distance between active rail line and the building (also allows improved site design/ access to the rear of the building).
All of the above items could be combined with the station function - but it makes better sense to put the station closer to city center and not tie improved rail service to a marginal development project isolated from the region's commercial/business/educational centers.