Though... If one were to take this to the limit and want to reinstate the full route and allow a call at Stockport Tiviot Dale
The express route was via Hazel Grove* and what is now the freight line (being as there was no Hazel Grove chord), before continuing through to Manchester Central via Chorlton-cum-Hardy.
There seems to be mixed messaging on whether trains would go to Buxton, or whether the plan is via Chinley. IF via Chinley, then using Marple might at least avoid some of the Stockport Viaduct pathing concerns.