As I have just completed 8 flights in the last couple of weeks, both domestically and in Europe, I will timidly venture an opinion here. (I love first class trains, Rosemary, you enjoy every minute!!), and I think the airliner coach experience may depend on the carrier and the length of flight. For instance the little Embrayers which they use here to get you to a large hub are wonderful, I think, the single leather seats (in coach), (the entire airplane is coach), United (formerly Continental) and anybody's policy of online check in and allowing you to choose your seats or change them even the night before, allowing you to have the first or second single seat in the plane is lovely.
I like Virgin Atlantic for overseas flights because they fly over to London in the daytime and you have no jet lag when you land. But this time to go to Europe from London instead of Alitalia I took British Air to Rome and back and was very impressed with their coach. I figured 2 1/2 hours or 2 hours how bad could it be? It was cheap, too.
It was nice! The seats were large, and the arm rests stayed in position (so Tubby next to you did too) and the best part was your stuff DID go under the seat in front of you which is new to me and much better than Alitalia where nothing including your feet fits under the seat. Even tho we were three on each side it was still pleasant and British Air insists upon feeding you and they even did free bottles of wine (I don't drink) but my two seat mates from Australia sure did, they each had 4 free little bottles and they weren't particularly mini, about 10 oz I'd say of Pinot. They were very nice people and quite interesting. They did hot panini for free, and tea or a soft drink, whatever you wanted. I was impressed, you don't get that domestically. I like their coach.
The worst problem for me on any flight is the people who have bags big enough to put gramdma in because they don't want to pay for a second bag and they either (1) get tagged, as they embark upon the plane and their bags are taken under the plane at that point, thus escaping the charge but having to wait for their bag to be brought to them at exiting the plane, or (2) they hog all the overhead bins so when you get on yours is full. I think they should be made to pay for any oversize bag going inside a plane, that would stop that.