That's not totally a yes or no question.
Technically the standard rating systems of the 18th century were not yet in use at the time, but some historians have made use of them to describe/classify earlier ships. Two schools of thought here are that 1) you simply apply the 18th century standard, (and by that means, yes the Zeven Provencien is a 2nd rate 80 gun ship of the line). However, 2) the second school of thought is that you apply the ratings according to what the nation fielded at that particular time. By that reckoning, the Zeven Provincien was a 1st rater. She was De Ruyter's own flagship of the Dutch Navy.
I tend to prefer the 2nd school of thought.
If we look at it this way, ships larger than 80 guns (Great ships or Kings ships) were not common during the 2nd Anglo-Dutch wars. There were only a handful of ships like the Sovereign of the Seas mounting 100+ guns in the English fleet. Indeed the Royal Charles was the English flagship, and she was an 80 gun ship. During the First Anglo-Dutch war, the Dutch were battered by the larger English ships, and determined not to allow that to happen again. Before the outset of the 2nd Dutch War, DeWitt had commissioned an entirely new navy be built, and by the beginning of the conflict,12 of the large 80 gun ships like Zeven Provincien had been built. The Dutch never favored ships any larger than these because of the shallow channels not only of the Zuider Zee, but many of the far flung ports in their vast colonial trading Empire. Their bottoms had a much shallower draft as a result making them much faster than the English ships.
The deeper keeled English ships enjoyed a slight advantage in choppy weather of a more stable gun platform, but several ran aground during the war as well. The Royal James was burned by the Dutch who couldn't wait to refloat her and feared the English would return in greater numbers to recapture her. The Dutch also enjoyed a significant advantage in fire power as well. The Dutch being the great arms traders, foundry builders, and cannon makers of the time, established THE standard gun sizes. Many of these were adopted into the English Navy. The Dutch 80 gun ships mounted either full batteries of 36 pounders, or 36's on the lower deck, and 24 pounders on the upper decks, whereas the English relied primarily on the 24 pounder with some ships having lower decks comprised of 32 pounder batteries.
By wars end, the Dutch had bult several dozen of the large 80 gun ships. At the Four Days Fight (1666), the largest age of sail cannon battle in history, it's reckoned that each side fielded over 180 ships respectively with some contemporary estimates guessing the total number of warships on the water at over 500. Most of the largest line of Battle Warships were present including the Zeven Provincien and the HMS Prince who engaged in their famous duel there.
In my mind the Zeven Provincien will always be a "First Rate" ship of the line despite her 80 gun battery.
MK
Its a huge lot of work to build a ship the size of the 7P, and it sure aint easy. but remember, its a community project, everybody can hop in and help, however me and Pedro are the only one's on it, and im pretty sure pedro works 40+ hours a week 