Open issues about the Dutch in the First Anglo-Dutch War

Perhaps, if I had complete access to the information, I would not have these issues. But given what I actually have to study, there are some open issues about the Dutch navy in the First Anglo-Dutch War that I would like to resolve. Some things would disappear from my list, if I just had complete information that is known to exist. For example, any information about the Rotterdam Directors' ship Erasmus, lost in June 1652. The dimensions of the other Rotterdam Directors' ships (the two ships named St. Pieter, the Prins, the Hollandia, the Meerman, and the Jonas). I also lack information about most of the hired ships of the Admiralty of the Noorderkwartier and the Admiralty of Rotterdam. I lack information about the later ships hired by the Noorderkwartier Directors in 1653. All that should be largely resolvable. Other nagging issues are actual details about Abraham van der Hulsts' ship in 1652, up to August. His ship was named Overijssel, but we don't really know the dimensions and guns, for sure. Then there is "Captain Belevelt", mentioned in lists in September 1653. He was said to be a captain of the Admiralty of Friesland. Carl Stapel suggested that Belevelt was a corruption of Bulter, that it was actually Joost Bulter. Was his ship, the Stad Groeningen en Ommelanden actually in service as early as September 1652? If so, it was with 28 guns, not the later 36 or 38 guns.