Couldn't agree more!
I think there should be more food cooked and served on board - EMT, GA, EC, WC, GW, and XC (and TPs longer routes) could all offer it.
Dining on board a train is special - particularly if the food is top notch.
Apart from the food, service, view etc, people seem to forget that it saves you time at either end of your journey too.
I can remember being very excited having my first meal on board a train. Was at college, saved up and had an evening meal on the train from St. Pancras to Sheffield in the 80s. Had a bog standard ticket (it was still called 2nd class then) and chose the cheapest things on the menu...... but had a great meal, in first class - a real experience!!
Dined on board a few times since then - GNER (excellent), BR (MML/XC TOC as it was) and on charter trains. You can't beat it.
And although not the cheapest - it is definitely VFM!