Can only offer some specific advice on a part of the route
I live a little bit south of Rotterdam and am familiar with most of this area:http://goo.gl/maps/u1w7H
If you want to pass through this area you'll be confronted with some E-W flowing rivers which act as big barriers. There's only a few points where you can cross. The westernmost route will take you along the dams that hold back the sea. Very nice, but windy and since the dominant wind direction is west to southwest it will affect you. Also, close to the coast can be really busy in summer.
A bit more inland there's more options. My preference would be the bridges at Willemstad, rather than the one at Moerdijk for the simple reason that the approaches are nicer (although you'll be riding on a parallel road to the main highway, so sharing it with local car traffic, the bridge at Moerdijk has dedicated bike paths on both sides).
Feel free to PM me for specific route suggestions.