I'll throw a line to Zizek. In his serious works, he does set out a systematic ontology of reality. I don't fully understand it, if there is even something to fully understand, but along the way he without doubt makes you think, and gives relatively accessible interpretations of a ton of other thinkers.
He's not a major philosopher like Kant, but he is much more than a charlatan or provocateur.
To his credit, I probably wouldn't have picked up his serious work if his antics hadn't first put him on my radar many years ago.