Hi Alex,
Thank you for your response and I understand the risk is there you'd be send away.
I actually just got back from the US yesterday and it was my third time traveling to the US since I130 application.
They really don't ask that much at customs, just what your reason for traveling is and when you're flying back.
If they want want more reason why you wouldn't stay longer, you can say that you are aware that if you overstay your ESTA it would hurt your visa case and you will likely never be able to travel to the US again.
I also carry a letter from our immigration lawyer stating the same.
Can't imagine anyone would send you back to NL after such a response, but like I said nobody has ever gone anywhere near that questioning me.
Cheers,
Paul