
In case of the Dutch, that is not entirely without reason, given the jokes you've had to suffer for so long now
To the matter at hand now.
I think a factor that some people overlook when talking about Dutch politics, is the complete collapse of GroenLinks (the Green Left). That party had kinda abandoned it's left-wing ideals (altough I was too young to take much interest in politics then, so maybe one of the senior members can correct me if I say anything wrong) and then participated in an agreement between the former government and several (centre right) opposition parties dubbed the Kunduz-agreement, in 2012. They had 10ish seats before that agreement and have like four seats now, so they have ceased to play any kind of a role in Dutch national politics. Other parties that have leftist ideals are not taken seriously (Party for Animals for example). That leaves PvdA, SP and Wilders' PVV. As you already described, PvdA lost most of it's electorate (potentially, we have yet to see the results) in the wake of their rather 'unfortunate' partnership with VVD. Now the big problem is that those votes have either gone to SP, PVV, or rightwing parties like D66. D66 is in a seat now, because no-one wants to form a coalition with SP (too leftist) and PVV (too anti-immigrants), leaving the left without any power at all. Yes, PVV and SP will likely grow, but until they together get more than 50% of the votes, the right-wing block that has emerged does not have to care about them at all. D66 will work with anyone except for the SP and PVV, so this puts them in an excelent position, especially since they have no problems with VVD and are likely to form a coalition in the future.
So the problem, as I see it, is that the left is fragmented while the right-wing parties are so many and powerful now that it's almost impossible that we won't see a right-wing coalition in the near future. PvdA and GroenLinks have effectively made themselves insignificant and the PVV helped them with that by stealing their votes.
It's quite a shame actually, because the PvdA was always the bridge between right and left. A strong PvdA will force all sides to move to the center and reach consensus, but with most of the centre left gone, they could not keep it up and, to govern, where forced to move to the right. Now D66 has more or less taken that role, but they are way further to the right so any coalition to develop is likely to be way to the right. That goes for national and local elections.
Careful readers will have noticed that I have implicitly called the PVV a leftist party. The prime minister just said that on the news

And it's true, as far as economics is concerned. The fact that they have (arguably) detestable ideas where foreigners are concerned, makes the left not want to co-operate with them.
Now, after this lengthy essay (

) on Dutch national politics (which maybe looks to be irrelevant and might not even be completely factual), let's get to the European elections. That right-wing parties, partially to keep power, have a very similar policy where the EU is concerned (and where most other things are concerned). Even D66 is in favor of giving more of our sovereignity to the EU (as Thorn said already, they will do anything for power). That leaves SP and PVV. Since the PVV presents itself as the most vocal opposer of the EU (the SP is a little more reserved) and has chances of succeeding (by an alliance with Le Pen), they will get the most votes. Also, the leap from VVD to PVV is not very hard to make, since both parties profile themselves as anti-left. What also contributes, is people have noticed that every centre right party they vote for is pretty much the same party with a different name. People know that this is not likely to change, so voting PVV in the European elections is also some kind of protest to what they view as the big neo-liberal conspiracy happening in national politics.
So, long story short: In my view, the complete collapse of everthing that can be called centre left has led to a reasonably powerful right wing and to the rise of more extreme parties. So, I agree mostly with your analysis, except that I think that the left (as a whole) has completely cut it's own throat because the two major opposition parties will never work together. And I DO think that the right-wing is going to capitalize. Meanwhile, the SP and PVV will continue to grow and they will continue to be ignored. Except where they seek coalitions with parties from other countries.