We can expect more babies from both Crown Princess Mary and Princess Letizia.
Letizia and Felipe have stated that they would like "more than two, less than five" children, and they just seem to be overjoyed with the two that they have- Felipe is more demonstrative with Leonor than he has ever been with anyone else- he still hasn't kissed Letizia publically even though they've been married over two years!
Mary and Frederik have stated that they wanted a large family many times since their relationship first went public. When they presented Lillepigen, reporters asked Mary if they would have more children, and I think her exact response was "Definately!". (I'll have to see if I can find that again)
I wouldn't be suprised to see another baby from Princess Lalla Salma of Morocco, although nothing has been stated publically, of course.
Who knows about the rest of the crown princesses? The only one I can guarantee will not have a baby is the Duchess of Cornwall