It really would be better if everything going through Central Manchester was co-ordinated to operate on a repeating clockface timetable every half-hour (trains wouldn't necessarily have to go to the same destination every thirty minutes, but the paths and stopping patterns should match for at least some of their journeys). This would make Castlefield more resilient, improve connections at Salford Crescent, and provide for more frequent services albeit to a narrower range of destinations.
Post Wigan to Bolton electrification, we should be looking at something like the following from the North and West:
From Bolton (4tph Victoria, 4tph Castlefield)
2tph Wigan North Western - Piccadilly - Hazel Grove
2tph Blackburn/Clitheroe - Victoria - Rochdale - Blackburn/Leeds via Dewsbury*
2tph Blackpool North - Piccadilly - Airport
2tph Scotland/Preston - Victoria
*1tph in each direction would operate as a circular to give Burnley and Accrington a faster service to Manchester
From Atherton (4tph Victoria)
2tph Southport - Victoria - Stalybridge
2tph Wigan Wallgate/Kirkby - Victoria - Rochdale
From Chat Moss (4tph Victoria, 2tph Castlefield)
2tph Cumbria/Liverpool Lime Street - Piccadilly - Airport
2tph Liverpool Lime Street - Victoria - York/Newcastle
2tph Chester - Victoria - Leeds via Bradford
From Warrington Central (4tph Castlefield)
2tph Liverpool Lime Street - Piccadilly - Nottingham/Cleethorpes
2tph Warrington Central - Oxford Road
This, plus 2tph from Hull/Middlesbrough via the Ordsall Chord, would give a combined 12tph at Oxford Road and 10tph at Piccadilly:
2tph Blackpool - Airport
2tph Cumbria/Liverpool - Airport
2tph Leeds - Airport
2tph Liverpool - Sheffield
2tph Wigan - Hazel Grove
2tph Warrington - Oxford Road
To the South and East, I would go for a similar idea of half-hourly pairs. For example, 2tph Piccadilly to Crewe via Styal could combine with the 6tph from Castlefield to give 8tph on the Airport branch, along with 2tph Alderley Edge to Piccadilly via Stockport.
2tph Piccadilly to Huddersfield calling at all stations from Stalybridge would allow TPE services from Victoria to be sped up, and the Llandudno service could be routed via Altrincham as in Option C of the consultation.
Adding the requirement for 1tph freight, this service pattern would give 13tph to Oxford Road and 11 tph through Piccadilly in the standard hour. This is 1tph more than the MRTF is willing to allow until the Oxford Road remodelling is delivered in the late 2020s, per the Manchester Rail Blueprint. Also I suspect that the 2tph Wigan - Hazel Grove, making a total of 4tph from Castlefield to the Stockport line, would create conflicts in the Piccadilly throat and/or at Slade Lane Jn, pending additional infrastructure improvements that the Blueprint places in the early 2030s.
Termination of Scotland/Preston services at Victoria would, as a minimum, require a west-facing bay platform at Victoria, scheduled for the mid-late 2020s in the Blueprint.
The Victoria TPE services are already non-stop between Stalybridge and Huddersfield. TPE has considered making both Piccadilly - Huddersfield services all stations between Stalybridge and Huddersfield, as the MRTF originally proposed, but that would slow Scarborough - Manchester journeys (assuming the Scarborough/Hull swap goes ahead) and increase performance risk. I believe it has been agreed that the intermediate stations will continue to get 2tph in the peaks, 1tph in the standard hour, as now.
The CLC stoppers need to terminate at Warrington West not Warrington Central, to satisfy local political requirements for cross-Warrington connectivity. This is dependent on new turnbacks at Warrington West and Birchwood (the latter for the Liverpool stoppers), which might be delivered in the mid-late 2020s.
I do not think it would be acceptable to link the Blackburn/Clitheroe via Darwen service with the Leeds via Brighouse. Running a long distance service through the single line sections would increase performance risk.
I also think it would be a retrograde step to divert the Scotland services to Victoria and to divert the Cumbria services back on to the old route via Wigan and Chat Moss, when they will have moved to the faster Bolton route from December 2022. From December, these services combine to provide a half hourly timetable between Manchester Airport and Lancaster, in line with your principles.
