We've been lots of time and it's my favourite park. I love the dreamflight (I can still remember the first time I took the boys on it - we were all "awww") and I'm sure your daughter will like it but maybe just not as much as she would have done when she was younger.
Just a word of warning, as it's an older park (Porto, indeed the one Walt Disney based his on) there is quite a lot based on walking around looking at things, mostly fairy tale stuff. I personally much prefer it to the loud, pure ride parks (even though I'm quite happy to get dragged onto go on most of them) but I would say that's a question of taste.
However, these days there are quite a few rides for older ones. The new Raveleijn looks good (it was being built last time we went there), the Bobbaan, the Python, Joris en de Draak and the Vogel Rok are all good fast rides.
If the French community holiday (27 September) falls on a weekday, we go then as it's less busy. We went last year for the first time in a while (27th had been a weekend for two years) and it poured down all day :(.
Porto, book 27th September as a holiday and we'll go together!