Careful on settling in mistalnds or running through most of them since you need an undiscovered one if they updated them, for iron farms I just park my boat facing the sea & head to the iron. Note that building a fire unless it is the big one it will go off & walking through swamps without rested is high risk, you could use potions but better to go with rested, find a spot where you can build a hut with fire for 8/10min rested.

I do sail literally at anytime of the day & find the spawn rate of wraiths to be low (up until now I have like 30 chains total), I'd call it a bad luck more than anything else but you could always use portals if the spawn is far away.