I don't think that the 40th birthday in Norway will be a big gala event. Ususally the heirs celebrate with more private parties.
Also I fear that the inauguration in Belgium will be much, much more solemn than it was in the Netherlands. From a jewellery point of view mainly brooches and some nice pearls .
Many state visits are only announced shortly before the take place. So there should be a couple of visits coming up.
My hope for a state visit: the new king of Belgium visiting the new king of the Netherlands, with two new Queens dazzling us to bits .