We can all dream, but for one reason or another, all ideas will be rejected. The planners will (probably correctly) tell us no paths are available; someone will tell that no stock is available; DfT will say "we didn't think about it, so it must be a bad idea", etc.
But in a dreamland world of infinite resources, here a few simple suggestions for my local area.
Liverpool Lime Street to Edinburgh, every 2 hours calling at St. Helens Central, Preston, Lancaster, Carlisle, Haymarket & Edinburgh.
Worked by Class 350/2 (with new 2+2 seating) when these become "spare". (Additional Wigan stop outside peak hours, to avoid peak services getting overloaded by "Wigan" commuters.)
Off -peak stops at Wigan to be reinstated for TP Manchester Airport/Scotland services.
Liverpool Lime St. - Manchester Airport semi-fast service via Chat Moss route (in addition to service via Warrington Central).
Hourly, calling at Huyton, St. Helens Jn., Earlestown, Newton Le Willows, Manchester Oxford Road, Piccadilly & Airport.
Liverpool Lime St - Manchester; All stations, 2 per hour, running alternately to Victoria & Piccadilly; these could continue to Stalybridge or Airport, respectively. (Lime St - Bank Quay withdrawn; additional journeys between Earlestown & Warrington being provided by Calder Valley - Chester services.)
Wigan Wallgate - Kirkby. Evening services to be reinstated.
(TP) Lea Green stops to be replaced by stops at St. Helens Junction. (Lea Green car park too small; spare space available at enlarged car park at St. Helens Jn.)
St. Helens Central to St. Helens Junction to be reinstated and electrified. LNW service London / Trent Valley to Crewe to be extended hourly to Preston, calling at Hartford, Warrington Bank Quay, Earlestown, St. Helens Jn, St. Helens Central, Wigan North Western, Leyland & Preston.