Psamathe wrote: I don't know if it was just because it is such a densely populated area, just because of my departure/destinations or because of the routing algorithms my GPS used to create routes.
Another thing I found (mainly in S) was that I'd create a route and set it to go via a town that maybe looked an interesting detour and I'd not look at where I'd be cycling through and on occasions I'd end-up cycling through miles and miles of built-up areas (housing, business parks, more housing, retail ...). On one ride I had 18 miles continuous built-up areas. So in creating your routes do look at what you are cycling through.
You've posted before about issues with your (I thought) Wahoo on a trip to NL and promised to write a review. Have you done that yet? I'd be interested to read it.
In any case, I'm fairly sure the issue was with your GPS device and not the routes. There are "main" routes everywhere, often beside the roads, but there are (longer) routes you can take avoiding almost all of those (knooppunt network).
As an example, the most direct route for me to work is 21 km, along roads. A pleasant cycle. For 500m longer I can cycle through a series of sand dunes/forests. No contest.
I use https://cycle.travel/map frequently and it works great too. Handy if you want to plan a round-trip. Tends to avoid town centres which can be a bit of a pain when they're very small, and besides, cycling in a town is not an issue here.
As to the OP, if you are considering a different route, bear in mind that it need not be a round-trip. For (I think) Euro 6,20 you can bring your bike on the train with you for a day - any destination. (You're extra!). That means you could, for example, grab a train to Maastricht and cycle back. Check out the Maas cycle route. I could imagine a lot of that being spectacular in Autumn.
Someone pointed out that a map was a good idea for when you lose the route (and you inevitably will, at some point). OSMand is an app that you can use offline (so long as you've downloaded the maps) to navigate, but also just to see where you are. By setting it up correctly, it'll show you the knoopunten (numbered signs that join together to make long routes) so you need never be lost and can make routes on the fly. Jot down the numbers and off you go.