I've stumbled upon this interesting topic before, of that I'm sure, but since I ought to study for my International private law exam I naturally researched some thing else:
anyway: I agree with the sentiment that the at to make the Netherlands a true great power the P.O.D. must be before the Westphalian Peace of 1648, it can still become a significant multi regional power.
If adhering strictly to "no POD prior to 1700", then the earliest you can go is either get Willem III remarried and fathering a son (imho, preferably with an Austrian/Spanish Habsburg) and/or having the Netherlands have more success in the Spanish war of succession of 1702. (Best have Willem live to survive this and get his son recognised as Stadthouder)
It was a fluke in OTL that the Spanish Netherlands went Austrian and it could end up Dutch. That would allow a significant boost to the Netherlands. Though the financial collapse of the Netherlands still needs to be prevented.
Having the Spanish Netherlands become Dutch partially prevents Austrian overextension. The price may be them rejoining the HRE (that would be in name only though). For that would "expand" the HRE and complete one of the Austrian war goals. It also should cement an alliance (protection) against France. This would put most (possibly all) of the XVII Netherlands under one banner again. Problem is France and also religion. Though imperial endorsement might be able to help with the religion bit. Especially since the emperor had some power with the pope.
Further options are to expand collonially: Open up the cape to settlers, or possibly grab some bits in South America (Cape Horn?). These colonies need be settler colonies to maintain Dutch power. Suriname too should be opened up and settlers stimulated. It is too late for a Dutch Brazil bit expansion isn't totally out of the question though.
Another useful POD would be the English and French losing population via illness or even civil war or combination missing the population difference for a short bit. Also it might help the Dutch get back some financial advantage over her biggest rivals.
Then there is the Napoleonic era in which a well played hand can put the Dutch a bit further towards the top. Either the House of Orange manages to keep Belgium and industrialises faster and can overcome the religious and language problem or it can be done by Louis Napoleon and a timely defection to the "Allies".
It is very important for the Netherlands, should it wish to be higher on the totem pole, that they either gain settler colonies or land in Europe. Preferably also get enough allies who fight the battles while the Dutch reap the rewards.
As to how far the Netherlands can expand into Germany/France is about the BeNeLux plus Nord Pas de Calais plus the Bakker-Schul Plan (areas where western low German is spoken). Same can be said for eaten expansion on the Belgian/Luxembourgian side, but one swiftly runs into the danger of this ATL Netherlands being more German than Dutch.
Colony wise, the colonies need to be retained until such time as technology allowed for complete integration but Africa and parts of South America may be places for expansion with 1700 as the earliest POD. I don't think the Netherlands can get enough Dutch speaking people to more settled/colonised places.
anyway, I should go studying again.