Hi!
I am the same and will ask any passenger to put their seat forward during the meal service, however if someone is asleep with their seat reclined during the meal service, i'm certainly not going to wake them and ask them to bring it upright, as it is their right to have it reclined. Unfortunately there's nothing you can really do in this situation. To be honest, i don't really understand the question, but....... If i have a passenger which is rather large and there tray table won't come down due to their stomach, i will usually discretely offer a pillow for them to put on their lap and then their tray on top of that. As for j/class pax, you can't really do too much either. If a large person is travelling in economy then they need to realise that they may have some space restrictions and may wish to consider purchasing a j/class seat instead, but that doesn't necessarily solve the tray table problem, luckily in j/class with the airline i work for, the tray table extends out quite far, so i haven't encountered that problem yet.
Oz