Woljif slays as long as you can micromanage him well and make sure he never gets focused on by enemy parties. A lot of his survival issues gets solved over time as you obtain better gear and pick up the mythic feat that enhances the Mage Armor spell.
If people are having a hard time figuring out how to level the companions, and have little experience with the Pathfinder system, I highly recommend keeping them single-classed. If you don't know what you're doing, multiclassing may screw you up in the long run as it means you may be delaying your progression towards key abilities. Lann's class for instance really blooms mid-late game when he gets more uses of Perfect Strike, along with free access to advanced archery feats without needing to meet the normal pre-requisites. His accuracy issues get fixed fairly quickly.
Also, I suspect some of the aformentioned accuracy issues are from having skills like Deadly Aim turned on. If you're having trouble hitting things, turn it off. IMO they're not worth using unless you're really confident about your hit rate, because doing no damage is always worse than doing less damage.
Ember is one of the most low key busted companions in the game. You want her Slumber hex on auto-cast, it lets her attempt to put an enemy to sleep once per day per target, and it works on everything but swarms as far as I've observed. Great for shutting down ranged enemies and allowing your melee to get free opportunity attacks. Her stat spread is also good for multiclassing her into a caster-focused Bard, though Slumber is much less potent there. Ember can also pick up another hex that allows her to ward a party member, and enemies that attack the target will essentially have the Pathfinder equivalent of disadvantage against them for the next round or so.
Thankfully there is a NPC that allows you to respec your party, though you can't respec companions starting from a level below what they join at.
Also, super small detail I never noticed in the beta. In the Shield Maze during the prologue, you'll occasionally see rats scurrying on the floor. Their movement isn't random - they will actively flee from the party if you approach them, calm down a fair distance away, and then scurry off again if you decide to continue chasing after them.
