Loving this game so far! Question:
I am leveling up fighter to get the extra carrying capacity, what skills transfer to other vocations....core skills?
I am just farming Grand Soren's area and have no idea where or what I am doing. Quest log is crowning...anyone have advice on which way to go to get some quests done and level up a bit? I am currently 16.
Every single augment can be used by every single class, although some classes obviously have little to no use for certain augments. Unless I'm mistaken core skills carry over to classes that share the same weapon; for example I went Mage(staff)>Sorcerer(archistaff)>Warrior(longsowrd)>Fighter(sword and shield)>Mystic Knight(staff/sword/mace and shield), so by the time I reached Mystic Knight I could use both the staff and sword and shield core skills from the get go.
As well as core skills, a lot of your abilities will transfer between classes that use the same weapon. However, not all of them will. For example, the Mage vocation can learn healing spells, but other vocations that can use the staff can't learn them/use them.
Quest wise I'd make sure to do:
Lost and Found (Received from the Chief in Cassardis. He's the old man)
This quest will be unavailable once you complete the second quest in Gran Soren; the first quest is just going to a place, then the second one is going into said place. Once you finish that second mission and leave this side quest will be unavailable, and will remove at least one important NPC from the game, as well as block off a part of the map completely.
Chasing Shadows (Received from Mason in Gran Soren)
This is only available after you do the second quest in Gran Soren. Completing this adds a merchant/shop in Gran Soren, and not completing this removes said merchant from the game.
Land of Opportunity, and Escort Duty (Both received from Fournival)
The first quest is available as soon as you get to Gran Soren, and the second one is available a bit later. Just keep checking with him until it's available. These deal with another important NPC, and the second quest gets you a useful item. However, I'd recommend looking at an FAQ for Escort Duty, because the mission is apparently very awkward in how specific you need to be to complete it.
Of course, I'd recommend doing all/as many side quests as you can, but these are the main ones you should complete.
Edit: Also, your level doesn't matter really. You're the same level if not 1 level higher than I was at that point. If you want to level up though your safest route is to just walk through that canyon that connects Gran Soren to the Encampment, and fight the Goblins, Harpies, Bandits, and Wolves on your way there. The cows in the fields outside Gran Soren are apparently a good way to raise Discipline Points without levelling up, but I never bothered with it.