Knight of calradia 说:
I would recommend going for 10 in trainer and tactics skills rather than into the main character boosting skills.,you should know this stuff, but I'll just say anyway what these two skills does, trainer: faster training depending of you character's level, tactics, increases your units performance in battles, super helpful.
Except both of those are exceptionally useless if you're soloing? You have no troops.
I've never soloed, but I would imagine the most efficient way for the sea raiders is to ride just around their maximum range, they'll waste a LOT of ammo like that. The longbows are harder, unless you've got a ranged weapon and can snipe them. Not sure how you'd deal with them.