overall, i'd say the wait was worth it, though i do have a few problems:

a lot of the attacks aren't balanced, in fact, i'd even call some chapter 4 enemy attacks FDY-like

chapter 3 minigames are boring

chapter 4 is way too long (seriously, with reading all dialogue, and without the secret boss, it took me almost 2 hours to beat it, and that's without dying once)

Toriel should've had a bigger role in chapter 3, i was hoping she'd be a playable character

but overall, the final encounter of chapter 4 was peak itself

and i enjoyed the chapters a lot

won't say who you fight as i don't wanna give spoilers