>Not showing much pride
Everything he did is informed by Pride. Dude believed he could improve on the grand design of reality, fucked it up. Tried to fix the scum of Humanity, fucked it up. Tried to keep his wife (not wholly clear yet), fucked it up. And he still had the gall to look down on Adam and Alastor, and his daughter had to take several first steps before Lucifer stopped jerking himself off with those fucking rubber ducks.
I like the fanfics where Lucifer proudly proclaiming "He is now in HIS house!" and promptly gets his shit pushed in by Adam. Because Viv is never going to let "Haha funny sad clown dad" catch an L.
Unironically, western civilization is suffering from success. If children had to spend some time outside the cities, deep in some godforsaken forest to learn how to survive in the wild, maybe they'd see Gluttony and Lust with scorn again because the former hoards food and the latter is too busy cooming to do his or her part of the work.