...but part of this is due to the fact that there are so many destinations from 13/14.
- Norwich
- Crewe via Airport
- Hazel Grove
- Alderley Edge via Stockport
- Middlesbrough
- Newcastle
- Glasgow/ Edinburgh
- WIndermere/ Barrow
- Blackpool
- Liverpool
- Southport
- Llandudno
If you simplified the route map, you wouldn't have the variety of passengers.
Look at how narrow a lot of London Underground platforms are, but they soak up passengers pretty quickly, because the vast majority of passengers will board the first train that arrives. Same with most light rail networks.
If the timetable had a simple timetable with eight well spaced trains per hour stopping at Deansgate/ Oxford Road/ Piccadilly and all stops to Manchester Airport (with the other two passenger services on the corridor being Liverpool - Sheffield), maybe with four of the Airport services running via Bolton/ Chorley/ Preston to Glasgow/ Edinburgh/ Cumbria/ Blackpool) and the other four running via Orsdall to Victoria and on to West Yorkshire then the majority of people would just board the first train that arrived (and, if not that one, the next one).
The problem that we have is all the hourly routes for Southport/ Llandudno etc - those services don't share any/many stops with the other current Castlefield services, so of course you're going to have congested platforms because people are hanging around waiting for that one specific service.
It'd be much easier to solve the busy platform situation by simplifying the mess of services - if we spend a hundred million pounds on ensuring that there's space for Llandudno/ Southport passengers to stand and wait for their hourly trains then that seems rather poor value for money to me.
I don't think it is worth the money - given that there are a load of other things we could spend it on (how much to wire up the CLC/ Bolton to Wigan/ Marple etc?) - building 15/16 would just keep Manchester addicted to a mess of hourly services and probably attract more (e.g. Bradford will demand an Airport service as well as Llandudno/ Southport etc keeping their Castlefield services - and if they get them then why not Calder Valley/ Burnley/ Blackburn etc?)