Ormskirk needs room for a 6-car Merseyrail formation of course (though the old emu bay only had room for 5 cars, hence the existence of 2-car sets among the old LMS units). The limiting factor is the Derby Street bridge.
It may be of interest that Ormskirk has both a Station Approach (the existing entrance) and a Station Road, which is on the other side, off Burscough Road. Nowadays Station Road just leads to a light industrial area, with no public access to the station. Clearly the down side building was the original station entrance, as Harrison and Sale's 1849 map and guide to the East Lancashire Railway suggests; it was on the town centre side, and is obviously the older building. The present station building on the up side looks Edwardian in date. Electrification reached Ormskirk in 1912, having taken 2 years to bridge the gap from Maghull, so it may date from around that time. It used to puzzle me in the 1950s, when changing to a Preston train at Ormskirk, that there was an unused ticket office on the down side. Though I have lived in the area for much of my life, I cannot recall ever seeing the down side building from the outside, or even a photo of it. There was a Rainford bay as well, now under the car park.