I've taken the angle, that since it's supposed to be replacement for the existing Chorlton facility in the District Centre, its proposed location makes it unsuitable because:
It is not as well serviced by public transport as the proposal makes out, with bus & Metro stops at least 400m away.
It adds about an hour to round trip times by public transport, so residents of central Chorlton will either; not bother going, or drive there.
Because their traffic forecasts rely on the fib that there are good local transport links, it is invalid, and will cause more traffic on routes that are already heavily congested (against environmental targets, and detrimental to the area).
Disabled, infirm, or those with small children will not be able to get there, other than by car (excluding minority groups).
Taking the Leisure Centre away from the District Centre is detrimental to the local experience, and to local traders and other leisure offerings (Against Council policy; South Mcr Strategic Regeneration Framework, Chorlton District Centre Action Plan 2010-2020, Local Transport Policy)
That the Council, in their "Feedback from December's information-sharing exercise" concede that the proposal does not offer adequate facilities (ie Sports Hall/ qty of Squash Courts etc) for those it's replacing, but that residents can travel around the region (to schools etc) (more traffic/ obstacles to use) rather than continue to benefit from a community-based resource, which could be improved/ rebuilt)
They also concede in the last paragraph of that page, that the centres of Chorlton & Withington are losing facilities, and despite this, on the basis of a misleading claim of the transport links of a field by a very busy A-Road is somehow a "good all-round solution".
I'm fairly sure the above are relevant planning objections; if the 'applicant' wasn't 'The Council', the Planning Dept also 'The Council', and the policies that are being casually cast aside 'The Council's', I'd be a little more confident!