I understand why some people feel it would be better for them to have a pve-only mode but I don't think that should be the way to go for SoT.
Since release I have been a solo player for the most part but also in certain occasions I managed to arrange voyages with a few friends and I really like that the game is both pve and pvp - It is a big part of what it makes this game special. You are required to learn and adapt in a world full of ruthless pirates: sometimes that means you might get to enjoy the views while sailing to a beautiful island to dig up a treasure, others it requires you to be on your toes and prepare a quick escape or defend yourself (it is your choice).
I have had a few encounters with an overpowered galleon full of pirates (thieves, griefers...) but never got my treasure stolen because I only let my guard down when I have nothing to loose. Nobody comes close unless I let them and everybody could learn to do so - I welcome thou (thee all) to sail with me and see for yourself =)
Again, I understand that some might just want to enjoy the awesomeness of this game without the worry of being attacked by other players whose only goal is to spoil other's enjoyment but if you think about it that is a perfectly valid type of behaviour you cerstainly should expect when dealing with pirates. It is part of the role-playing fantasy of SoT.
Having pvp opt-out options would certainly break the magic that this game has - gone would be those emerging gameplay moments where you need to execute your escape plan because a galleon is approaching or the uncertainty of meeting somewhere in the wild expecting the worst and see it ending in music playing and dancing.
It would surely result in one group of people sailing on their own, climbing faction ranks and enjoying the gorgeous view but having all uncertainty removed as once you learn the game systems you would not have a hard time surviving it all (storms, skeletons, kraken...) and then you would also have a separate group in large galleons shooting at each others for no reason (no treasures to gain as this are people only interested in ship hunting) - that role play of big ship full of ruthless pirates chasing smaller ships to steal treasure would forever lost.
Perhaps if another AI controlled ships were introduced -like merchants that can be intercepted or pirate hunters that will engage in combat with players, it could help to shift the focus of these ruthless pirates/griefers away from other players enough to make it more pleasant for those that prefer not to engage on pvp.
Another solution, in this case for the camping on outposts "issue", could be having ONE big output be a pirate sanctuary somewhere in the map that has AI defences an no-fire restricted area in which players are safer - if somebody breaks the no-fire the will be attacked by the AI; with this players could have two options: risk it in nearest standard outpost or travel farther and be safer.
I think the small vessel needs to have one more cannon at each side (when playing two on a ship) so if one is forced to defend it feels a bit more balanced as right now is 1 cannon vs 4 cannons when a galleon attacks you.
In summary, I am all up for improvements that makes things better but I really hope they never divide the community into pve and pvp groups as particularly in this game, it is part of what creates the fantasy of a sea full of pirates/thieves a compelling and believable one.
Sea you all arghhh there captains!