Time changes everything. That certainly goes for the way you feel about the books you've read. It also changes the way you feel about books that you've always wanted to read and are just now getting around to reading.
I like and agree with your review. Remember when the book was written it was a much more naive time, not just for us, but for the world as well. We were still practicing for the Russian invasion.
How can you not love a character named Kilgore Trout? Mr. Vonnegut was nothing if not "trip-y".