I've done most of the chapter 1 areas. Everyone says that the companions are shit, and they kind of are:
-Amiri can't hit shit and she dies instantly. I tried different stuff with her, but ended up doing an Inquistor Huntsmaster, because she at least has an animal companion. Beyond that, whenever I take her on a mission, I often find that I just give her a bow and let her not hit shit at range, as she has a bad habit of perma-dying.
-Valerie's fine. She can at least tank shit almost infinitely, although she rarely hits anything. I feel like she might get better as I start building out her offensive skills.
-Regongar is shit. He gets hit once and he perma-dies. So basically useless.
-Linzi is shit for offense (save for daze, which she can spam infinitely on humans, which is awesome), but her support spells are fine. The bard spells make a big difference.
-I haven't used Octavia much yet, but her starting, vanilla, spells aren't terribly useful, so I haven't been using her much. She could maybe be good, but she's hasn't leveled for me yet so I don't know what spells come as options for her class.
-I've hired one Mercenary Sorcerer who's basically all Grease Casting, all the time. Grease is pretty insane as it's very OP, but all my melee people get caught in it, so it's very unpredictable. I've had some insane edge of the seat battles where my melee people took turns with the enemy repeatedly slipping in the grease.
-My player character has actually ended up being the main DPS on my team. Bows are pretty good once you get the rapid shot feat and the feat that increases your attack when enemies are engaged in melee.
-I just got the Cleric guy (Tristian?). That temple where you recruit him was insane. There was the bear, the warthog, and then the 3 massive wolves, which I thought I had no chance of beating, but then I parked all of my people on the upper left ledge of the temple, cast the vines and a bunch of grease spills on the steps, ran my leopard companion down to aggro them, and then my entire team sniped them as they got caught in the vines and slipped on the grease. It was awesome.