I mean the three stations selected are a bit random.One thing Rotherham should concentrate on is an improvement of transport to the airport. A station would be perfect, but as we aren't in the SE, some sort of dedicated tram / trackless tram from South Parkway. He has hinted on Twitter " watch this space " also an improvement for access to Anfield.
The one I know most about is Woodchurch and have always thought that this is not an easy build, given the height of the railway line above the road.
In addition, with an every 45 minutes service and a change at Bidston for Liverpool, it is difficult to see where its passenger base will be.
As has been said above, people will not head out of suburban Birkenhead (e.g. Prenton, Oxton) away from Liverpool to use it to travel to Liverpool.
Whilst there is some potential as a West Wirral park and ride, those in central West Wirral (e.g. Greasby, Irby) will likely continue to use Birkenhead North (and to lesser extent Bidston) Park and Ride with a much more frequent service. Those in south West Wirral (e.g. Heswall) will probably continue to use Spital (ditto much better service).