Ten days, that gives you a lot of possibilities. I am going to approach this practically and suggest the route from Millingen aan de Rijn to the south, Maastricht (262 km). I have a couple of reasons for this choice.
First, I walked it myself and found it very beautiful. It is the southern part of the Pieterpad, by far the most well known (and liked) long distance walking route in the Netherlands. It also more or less follows the direction of the Way of St. James Limburg (Jacobspad Limburg, 222,5 km). But the latter is less traveled, not as well waymarked and skips some gorgeous country-side bits. Plus stamps for a credential (which you can get) seem to be a hassle to get.
Which brings me to the second reason for my choice: accommodation. The Pieterpad is mainly so popular because it consists of easy 20 km (+/-) stages, beginning- and endpoints being very accessible with public transportation. And because it is so well known, plenty of choice for B&B's, hotels and campsites (the last with occasional lodges or caravans for rent).
Reason three: the south part of the Pieterpad has much more amenities than the north part. So less to worry about, less planning required and a lot more cafés, restaurants and the likes. Just walk and enjoy. I'll link some relevant sites for you to find out more. By the way, no credential needed.
Lastly, from Maastricht you can access the Via Mosana to connect you to the Via Monastica to get you underway from the Netherlands all the way to Santiago. A nice thought to dream about for later years.
Happy planning!
Way of St.James
Limburg
Pieterpad
site (+
halting-places -
accommodation listings -
guide)