It sounds as though the OP is interested in slowing down and paring back a little but is not sure how.
It's very hard for us to advise you since we can only infer your priorities. Sometimes destinations that are logistically "inefficient" (that is, they don't fit in to the itinerary very well and take a long time to get to and from) can be the most rewarding.
You seem to have a broad swath north of the Alps that ought to fit together pretty well. For out outliers, though, I would suggest asking two questions:
- Does this destination justify the time, trouble, and expense of getting there and on the the next?
- Am I spending enough time at this destination to justify the time, trouble, and expense of getting there?
If the answer to either is no, then it's a candidate to save for another trip. If the answer to 2 is no, it's alternatively a candidate to add a day or two.
For instance: I will observe that 3 nights in the Bernese Oberland is at best risky. If you have a day of bad weather you will only have a day for mountain sightseeing. Better than none, but I should regret coming all that way for so little. 4 nights hedges your bets better, and should the weather be stellar the whole time you get a bonus.
Venice, Prague, Pula are other places to at least think about on those terms.
You may also wish to ask if you are spending enough time visiting some of your other destinations. Haarlem is, I assume, a base from which to visit Amsterdam. Of course you can have a very full and interesting day at any of these great cities, but you will hardly exhaust them. A second full day would also be rewarding, and even a more.
You are spending a lot of money and effort to visit these fabulous places. So, do not sell yourself short by leaving too soon!
Of course, only you and yours can know where the sweet spots are. But sit down together with a map and a sense of the cost in time and euros of your transit connections. Then be brutally honest with yourselves. You'll have a better trip if you do.