Slaughterhouse Five is a more challenging book, and more effort to read. I honestly can't tell you if it would be worth the effort for you.
Cat's Cradle is a somewhat easier read. I'd suggest trying that next, and if you like that, give Slaughterhouse Five another try.
As for sibling post, strong disagree WRT Douglas Adams. ducks. Unpopular opinion, I know, but your description of Vonnegut is curiously similar to how I might describe Adams. His supporters are enthusiastic and vocal. I wonder how large the group of silent dissenters is?