Using GMC and B-Frames is probably a good idea, Using Q-Pel probably wont help that much, but it makes the video slow in decoding, so it's porbably not worth it.
Psy enhancements are no longer broken, so it should be fine to use, though I wouldn't recommend it except at low bitrates.
Film effect adds the sort of effects you see in the movies, like grain. It doesn't improve the video, but people sometimes like them better. Sort of like how some people prefer LP's to CD's because they are used to the artifacts of them.