It's a bit of a long one, but I hope something is useful...
If you can, get a Virgin pendolino. Apart from catering, they have far more space in 1st than any other option. (On TPE, it's half a carriage, with people constantly walking through to use the toilet).
You will probably find that you are booked in coach H, which may be mostly full. In my experience staff are quite happy for you to go and find more space in another coach, and have even suggested it themselves.
If changing at Wigan, it may be more comfortable to take the stopper. The 'fast' train will probably be a 2-car (diesel) train, which comes from Blackpool and will be mostly full. The stopper starts at Wigan, and should be a 4-car (electric) train, so will likely have more space.
As for hotels...
I am rather fond of the Adelphi, but you have to know what to expect. It is a formerly grand hotel that has not been looked after properly for many years, and is mostly a budget or coach-party hotel these days.
Some of the rooms are cramped, dated, stuffy, windowless, and noisy.
However, some of the rooms offer a great piece of history for a good price. On my last stay I had a magnificent, huge, 4-poster suite, with enormous high ceilings, a wood-panelled hallway and walk-in wardrobe, next door to Harold Wilson's old room. All for £35 a night. (I booked a standard room, and offered to pay for an upgrade at check-in. The man on the desk upgraded me but declined payment).
A good option is Accor's 'Happy Mondays' rate. Every week, from midnight Sunday to Tuesday you can book rooms for the following weekend (Fri/Sat/Sun). If there is no football game on, you can often get the Novotel for £40, or the Ibis / Ibis styles for £25. (Liverpool games have more of an effect on hotel room prices, but they have no home games at the end of March).
I would, however, have a flexible booking as backup if you are going to try this, the city can fill up and end up being rather expensive.
There are a number of Travelodge / Premier Inns in very good locations. But be aware that Liverpool is something of a 'party' destination and they may be noisy at weekends.
Beware of hotels that specifically cater to large groups unless you like all-night noise!
The Crowne Plaza at the airport is quite nice, and interesting (art-deco former airport terminal). But it's a 30ish minute bus ride to the city, and not a place you would want to wander round at night.
I quite like the Hilton, it's very modern, and a great location for the shops and Albert Dock. The executive lounge is also a nice spot to sit and watch the city.
The Crowne Plaza in the city is a nice quiet spot, near the city, but it's a little isolated at night & weekends.
There are some hotels around the Convention centre - Staybridge Suites, Jury's and the new Pullman). Again, it's a nice spot, pretty close to the action, but slightly isolated at night.
The Liner is ok and in a good location; rooms are small, and service can be a little spotty. The squeal of rail noise can be a problem if you are on the station side (trains start at around 5:20am)
If you give some more idea of budget, or what sort of thing you are looking for, there may be some other suggestions. (Maybe the trip planning forum is more appropriate for more detailed discussions).