Belgium Netherlands Tour Itinerary - Need suggestions

I've not been to Antwerp but I might just visit that on the way to Ghent and spend that night and the 1st night you have for Bruges in Ghent. There is a lot to see in Ghent and I do recommend going to the Fine Arts Museum there to see the art restorers working on the Van Eyck Altarpiece. I found it mesmerizing to see them work with what looks like Q-tips and dental picks on teeny-tiny patches. Then to see the Altarpiece at St Bavo/Sint-Baaf's was really fantastic.

I'm not big on one-night stays which is why I suggested 2 nights in Ghent instead of just one.

I also thought Bruges was much prettier than Ghent altho I know many here recommend Ghent over Bruges. I was on a RS tour and we spent 3 nights there and still didn't get everything done I wanted to do. The museum pass for Bruges is very helpful.

I also enjoyed the Mauritshuis Museum in Den Haag. I did it in an afternoon from Delft - very easy 25 minute tram ride. I very much enjoyed the old city core of Delft. Wish I had had time to do the Vermeer Experience there. None of his paintings but several tour mates did it and found it fascinating.

One thing I planned to do from Bruges was take the train out to Ostend and see the Atlantikwall. I cut this idea when I realized how much I wanted to see in Bruges but you might have time if you have a WWII interest. There is a tram that runs along the shore from which you can access the wall.

https://en.wikipedia.org/wiki/Atlantic_Wall_open-air_museum

We did a tour of Flanders fields on the RS tour and it was very interesting. We did the American Cemetery, Essex Farm cemetery, the German Cemetery at Landgemarck where the Germans first used a gas attack. Also wound up the day with a visit to Tyne Cot Cemetery and a location where you can see and go in the trenches. Yikes. We did not see the end of day ceremony at Menin Gate which I understand is very good.

Do your WW I sight plans include places in, and around Ieper (Ypres) ? The In Flanders Fields Myseum, the town square, and the WW I memorial are worthy visits. If you can stick around until 8pm, there’s a daily Last Post ceremony at the Menin Gate, remembering the War Dead.

We did the trip from Brugge to Ieper by bike over several days (rented from a shop in Brussels) so we traveled a lot slower than you will by car. Possible stops en route, for a break or a meal, are Kortrijk (Courtrai) and/or Diksmuide (Dixmude).

It looks like you have a great itinerary.
Rotterdam is a very new and modern city compared to other parts of the Netherlands. If I were to drop a city, that would be my choice. You can also day trip to Haarlem from Amsterdam.

In Utrecht, if you want a rice table, try Blauw; they also have a location in Amsterdam.
Don't know what you are considering for accommodations; if you are staying someplace for a number of nights, many posters like Air BnB establishments. We used VRBO and rented a house in Zaandaam, just outside of Amsterdam. It was a convenient place to use as a base.
We really liked Ghent last year and stayed at the Hotel Carlton, a fine establishment run by two brothers; they offer a fabulous breakfast and their conceirge services are top notch. they are very knowledgeable about the area, including Bruges. I would stay in Ghent and day trip to Bruges or at least consider spending more time there. Be sure to see the Adoration of the Lambs at Sint Baaf's Cathedral. The architecture of the cathedral is a marvel.
Have fun planning!