I very rarely sit at a table to eat these days and the last time was at Xmas, but what bugs you etiquette wise? I hate it when people eat with their mouths open and noisy eaters.
Re: overloading plates - a few years ago I had the misfortune to go to an all-inclusive resort in Egypt, and unknown to me the Russians had arrived (awful people - if I never meet a Russian again it will be too soon). They went further than overloading their plates, they overloaded their tables, and then left about 80% of it untouched and you'd see the waiting staff come round and shovel it into bins.