Most chances we will not have any big surprise in group stage but with things are moved into knock out then surely few surprises can happen because many teams are capable of giving surprises, and we can't predict right now about these results with every one is talking about the Netherlands and Belgium here most chances Netherlands can go into last four but after this they have never been lucky to have better results even their quality is at their best, but their luck is surely not good as they need with Belgium is also having quality, but things are not looking good for them to have better result for going at the top I am preferring Croatia because they are better and capable of giving shocking results in any condition odds may be never been important as bookmakers mostly going with their own system.
We have seen even group stages having some sort of shocking results before, but most of the time you are right that it won't be shocking too much. Knock out stages could be shocking because it’s just one game, meaning that teams who are better and favourites, could underrate their opponents and end up losing and reversing that in the game itself is not easy, it takes time to come out again and be better.
I still think that one of the favourites will win the cup though, even if there are some shocking results, it will be one of the favourites of the cup that will not have any shocking results and end up winning the title easily.