Textually 'rich' books like Good Omens and others like Terry Pratchett? Things like footnotes, lots of parentheticals, simultaneous and converging narratives, unreliable narrators?

I really loved reading Good Omens but want to try out some similar books that AREN'T by Terry Pratchett, LOL. I loved the excess of details to follow, watching multiple distinct but related narratives eventually converge, and especially loved the fun of footnotes. I don't mind a more serious or darker book, but would prefer it to be at least a little witty.

EDIT: Thank you so much everyone for the recommendation! I've got several of these books on hold at my local library and will definitely try them out.

EDIT 2: I’ve reached the hold limit on my library card, LOL, so if you’re seeing this I’ll probably get to your recommendation a lot later rather than sooner, but thank you so much everyone for everything!!