Lelystad (EHLE) is a great destination for GA pilots in the Netherlands. It’s very GA-friendly but still has customs on site and (relatively) cheap landing fees compared to Schiphol or Rotterdam. The aviation museum, pilot shop and cafe with terrace make it a nice place to spend a day if you’re a pilot or aviation enthusiast.
Anywhere I have to pay a landing fee for an SR-22 is most assuredly not "GA-friendly" but that's why I live in the good old USA.
You're very lucky living in the US. We have to pay for everything here. Even renewing our licences (not the checkride or anything but just the paperwork). In Holland, landing a Rotterdam or Schiphol can cost more than 200 euros. In the UK, there are several airports that don't just charge landing fees they also charge for touch-and-go's or aborted approaches. Flying here is very, very expensive.