I would say the buccaneer is the best for soloing. They are a pretty well rounded class and also get one of the best companions in the game (peter quint) early on. Best origin would be grizzle since it gives naturally tough. How you lost your parents is really up to which companion you prefer.
i was wondering what you guys think the best pirate for soloing is. So like which class/origin/how you lost your parents etc.
Soloing? I'm biased, but Privateer I think. I constructed mine to be a Jack-of-all-trades character, so I have some abilities from every class, but we'll get to that later. Origin I'd say from Krokotopia, Mooshu, or Grizzleheim as all three are beneficial to Privateer capabilities. Lost parents I'd say Shipwrecked, as Russel can be a very very flexible character in construction, he can tank or dps (I personally make him tank, and fill in attack with Privy buffs).
For constructing early game, I'd hit up either the Buccaneer, Swash, or Witchdoctor. I personally trained in Musketeer in addition to these three, but only so that I could equip every weapon availible in the game. But those three are largely in alignment with what you'll be doing. However, if you want to be a primarily support privy who doesn't get his/her hands dirty, go Witchdoctor and do Krokotopia. Both use Spooky incredibly. As a side note: Slashy/Staffy isn't that hard to find. Beyond that... not much advice I can give.
I have soloed this game with all classes of pirates ( across two accounts ). Every class has advantages and disadvantages depending on the enemies I was facing. Any class is good for soloing, there is no "best".
Best for soloing is going to depend on your play style. Swashies and Buckies are great for a run-up and thump things player, while witchies and muskies are better if you like to stand back and direct battles from the rear. Privateers are probably the most flexible, in that they can boost their troops and offer lots of healing, but are pretty good in a toe-to-toe slugfest as well.
So far I've soloed every class up to Aquila, and to be honest, they're all equally good. They may struggle in different worlds based on class, but as long as you keep your crew up to scratch they are all good and a lot of fun to play.