the closing was pretty lame. except for the number of people, there was nothing else that spectacular and the singing was annoying. london could easily beat these games. their venues will be better (except for their main stadium, which does not look anywhere near as impressive as the birds nest) and they will definitely be freer games.
the quote thing was started by rogge in athens. he said that unlike samaranch, he would never say that any games were the 'best', but would come up with a descriptive name, so athens had 'dream' games and beijing had 'exceptional' games.
as for the greek flag, etc. it's all part of the tradition that has been building over time. the whole idea of marching, a torch relay, a flag to pass on between host cities have been added on over time, and i think it should stay. after all, the games were intended to be held in greece every year, but de coubertin wanted them held in france at least once, and then everyone else said why not just continue with it moving round the world.