I read them in college and thought they were okay. They’re very easy reads, but are fun and have some solid twists and turns. The love triangle is overdone, but that’s the YA genre.
Red Rising might be up your alley too. The first book is sort of like a more interesting, more adult Hunger Games. The series gets quite a bit different after that, although they both sort of have the same premise of a class uprising inspired by one rebel figure.
I’d say to check out It and The Stand, which are generally regarded as two of his best novels. 11/22/63 is excellent as well, although it’s not really a horror novel. Pet Semetary is good too, and quite a bit closer to Salem’s Lot than much of the King stuff you’ve read.
Honestly, the bulk of his older stuff is pretty good. His newer stuff tends to be more hit or miss.