The ending of Utopia is famously ambiguous, and also, a bit anti-climactic. So don't worry if you finished the book with a bit of a huh?
For centuries, people have found the ending frustrating because after reading pages (and pages and pages) of all this info on Utopia, we never get much of a sense of what our narrator and author, Thomas More, thinks of it all. All he says is that some things seem silly, a few things seem okay, and he doubts anything will change. Bit of a downer.
The biggest question of all is, if More has this lukewarm attitude about Utopia, why'd he write this whole book? It's one thing to write a book about somewhere great, it's another to write a book about somewhere horrible, but why write a book about somewhere sort of average, with good and bad?
We are so with you on the frustration, but there are a few ways to look at it that might help. First, there is some pretty controversial stuff in this book, especially for More's time. So the ending allows More, the person, who works for the king and doesn't really want to get into trouble, to distance himself from Hythloday's opinions. More can just be like "I'm reporting what I heard! Don't shoot the messenger!"
Second, just like the ambiguity of the title, More wants his readers to do some thinking on their own. He doesn't want to just spoon feed us answers for how to be good. Instead, he wants this book to spark debate and force people to think about these important issues. So go on, be frustrated, go debate-it-out with some friends. More would be thrilled.