Origin Characters - 'Hi, I'm <insert name>. I have a dark and mysterious past, which you aren't allowed to know, until you randomly choose things I might approve of. Once I approve enough of your random choices, I will tell you everything about myself and burden you with my sidequ... I mean, my deep and mysterious problem, which you will have to help me with.'
To be honest, every character is the same character, which is why they are unlikeable. They are ALL hiding something, and hiding it badly. Vampire (Astarion), Insecurity/Need to prove my worth (Laezel), Magic nuclear bomb (Gale), 'Secret' agent of Shar (Shadowheart), Pact with the Succubus (Wyll). And they all want to sleep with you, for no real reasons at all seemingly other than being horny. Can't they sleep with each other? Or a party guest?
The secretive Shar worshipper is the only one telling you all her secrets at every turn, despite the fact being a Shar worshipper means you don't tell anyone, anything, ever. They are basically secret agents. It should scare the piss out of Shadowheart that you have a mind connection using the tadpole, because it'd give you access to her secrets potentially. But she groups with you anyway, and that's all to get the maguffin special object the plot will revolve around to the PC.
I don't like any of the companions personally, or their side quests - Gales is particularly stupid, sacrificing magic items to him makes finding any loot almost annoying. And I don't like the fact you are all from the same ship at the start, but you only see 2 of them in it.