Faber's game feels pretty antiquated but we never really got to see him, in his prime at 135lbs. He was a damn good all-rounder, athletic, aggressive, high paced, great cardio, aggressive standup, solid wrestling and great grappling. He was in his late 30s and near the tail end of his career but his wins over Saenz and Simon aged well, Saenz around that time beat Merab Dvalishvili and was a solid D1 wrestler Simon ended up becoming a top 10 level dude. I know Faber vs Cruz 1, Faber obviously won by submission but the rematch at 135lbs when Cruz was champion in 2011 was super back and forth, I remember people arguing over who won that fight at the time. We just saw how an old, shopworn, injury ridden Cruz looked vs Chito Vera winning rounds and outworking the guy until getting caught in the 4th.
I'd favor Aljo, but there's a lot of reason to believe you take a 27 year old Urijah Faber in his prime and drop him in the 135lb division today he'd probably be good enough to contend for a title.