Yes it is predictable, yes the pranks are sometimes stupid etc. But do not tell me that you had high expectations for the plot? You knew this would be a simple and straightforward movie with an uncomplicated plot. You have a supercast, Robert De Niro, Uma Thurman, Rob Riggle, Jane Seymour and Christopher Walken. It is the same as going to see a LA Lakers game to see LeBron James playing. And at the same time you can enjoy watching the other superstars from the Lakers like Anthony Davis and Danny Green.
This movie is very enjoyable to watch. Don´t have high expectations and you will be all right.