I loved the Paris scene with the 70's Super 8 4:3 camera inclusions as it made it feel more realistic and gave the film a style and when Erik is dragging mystique along the ground with the bullet in her leg then ripping it out. Ouch!
I also liked the flashbacks to previous films with Logan seeing young Stryker and having flashbacks to Weapon X and Brian Cox 'I just saw someone who will bring me a lot of pain someday'.
As well as young Charles seeing Logan kill Jean 'You poor man, I don't want your suffering, I don't want your future!'