I’m a noob, so obviously I don’t know shit lol.
But, going off what what sounds difficult to me (it may not be) and your current song choice, maybe something from In Flames, Parkway Drive (they’ve got some kick ass rhythms I wish I could play lol) or maybe for a more melodic feel...nevermore (although Loomis plays a 7 string)
And of course, ya know....Metallica. Lol. They do have some harder rhythms (in my opinion) on songs like Dyers Eve, Blackend, and of course the obligatory mention of master of puppets.