I'll toss in a couple of off peninsula spots that I think would work well for a stadium.
The first pictured area is about 500 metres from a proposed fast ferry station at Shannon Park. The second pictured area would have multiple ingress/egress options and due to its elevation, would offer views of the city centre.
Both sites would offer beautiful east coast water views suitable for a team called the "Atlantic Sharks".
I doubt the current proponents would be interested in building a stadium at either site this close to downtown as there'd be no profit or at least a much reduced profit from their proposed hotels, bars and restaurants due to existing competition. They're looking to build a profitable entertainment district not a profitable stadium. Is it even possible to build a profitable stadium?
50 plus empty acres by
A.J. Forsythe, on Flickr
614 Acres UR by
A.J. Forsythe, on Flickr