It was never 323's, I can't recall 158's on it, before 170's it was loco hauled Mk2D's etc. or an HST. Most of the services were Inter City. You obviously can't remember Liverpool before it was downgraded to a branch off the WCML. Ha ha.
Yes there were 323s - before Central joined the Liverpool and Stansted services and went diesel throughout.
2+3 323s on Birmingham-Liverpool were definitely downmarket (but then they also used 310s on Birmingham-Manchester for a while).
2+3 350/2s aren't much better, but 350/1 are as good as anything previous and can do 110mph if they want.
The trouble with the current service is the hanging around at Crewe southbound, only to get caught up in congestion later.
One service is turned slow line at Wavertree and back at Speke just to avoid Allerton Jn, and the other is now timed to use the slow line (at least now 100mph) between Crewe and Stafford.
And (compared to the Manchester run) they stop at Penkridge and Coseley or Galton Bridge.
These trains invariably lose time in the West Midlands, but have time to kill north of Stafford.