Similar as posted in another thread a while ago:
1) Liverpool Central - Kirkby extended to Wigan Wallgate (every 30 minutes) and Skelmersdale (every 30 minutes), with southward extension into Wapping Tunnel/Edge Hill
2) Southport - Hunts Cross extended to Warrington Central. Possibly post NPR/HS3 when minds are finally made up as to what form the Transpennine upgrade east of Manchester takes.
3) Liverpool Central - Ormskirk extended every 30 minutes to each of Preston and Burscough Bridge/Southport. Midge Hall station reopened (trains already stop there to pick up/drop off the token for the single track section to/from Rufford). If extended beyond Burscough Bridge to Southport, New Lane and Bescar Lane to have trains calling every 60 minutes at each (maybe on request), alternating between them (it is unlikely anybody would make a journey between those two stations as it is a fair hike to the exact same main road that passes both). Also, extended south of Central towards Gateacre.
4) Bidston - Wrexham Central extended to Birkenhead North, and increased to run every 30 minutes. With some creative timetabling, trains would be timed to pass each other more or less at the same time at Shotton upstairs, with downstairs (the ex Chester & Holyhead/North Wales Coast) having the Liverpool Lime Street - Llandudno (every 60 minutes) and the Manchester Pic - Bangor (Gwynedd)/Caernarfon via Warrington Bank Quay (every 60 minutes) timetabled to more or less pass each other at Shotton, calling there 15 minutes either side from upstairs. This would provide a far more friendlier interchange with the other three directions rather than a 55/5 minute interchange time.