What I've learned over my years of playing at an amateur level... sometimes the easiest songs are the hardest to play. Because then it's really the small details that make it sound best. Precise exact inflection to provide the proper space within the notes, and tone is such a huge huge part of those easier songs you've mentioned. The way Dean plays Meatplow is positively FILTHY. The notes are easy and it's a relatively straight forward song, but I still can't play it anywhere close to the way he plays it. His fingering style and his tone on that song are just grime.