I'd say let the developer build density, but try to negotiate maximum parkland as part of the development but also try to secure some Section 37 funds to invest in the other parks around the city.
I know this is probably a pipe dream.. but I think a large part of the lack of access to parkland problem the city has can be solved or reduced greatly by constructing a pedestrian and transit bridge from downtown to the Toronto Islands. The Islands are a huge parkland asset to the city that is very under utilized (from the unfair leases on the houses that sit on the island as well as the park design and ecological preservation). The bridge could possible be done from either the Portlands (Extend the Broadview/Cherry Street Car route) or from Bathurst and Queens Quay area (Extend the Bathurst Street car route). Or both..
Take a look at the size of the islands compared to the billion dollar knockoff highline the city wants to create.
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