I think that at higher levels order of the souls can be easier then gold hoarders. This is because at higher levels in gold hoarders you have cursed chests such as the chest of sorrow which slows down your progress but in order of the souls you don't have that problem.
So I propose that you should add cursed skulls to the order of the souls missions. And here's a couple ways you could do that.
First of you could have the devil's skull which looks a bit like a foul bounty skull. When on your ship this will act a bit like a chest of sorrow and every now and then you'll here the sound of fire but instead of taking on water you'll start taking damage.
Secondly you could add the serpent skull which as a snake on the top of the skull. This would work like the barrel of a thousand grogs but instead of making you drunk when you pick it up it fires snake venom at you but this snake venom doesnt do damage it just blinds you.
I hope you take my thoughts into consideration and if you don't like my ideas I'm sure you will find a way to even out the gold hoarders and order of the souls.
