When I say it doesn't make sense for her to sat on the team, I meant that she should ditch the team as soon as we stop going right to the creche at all. She pointedly says she doesn't value us or need us, so it's pretty contradictory that she sticks around us when we don't do as she says. She should just kill us in our sleep and go off on her own as soon as we question zorru. and if we don't interrogate him the way she wants, the even more reason for her to leave.
I think you've maybe got a wrong take on Laezel here, Gray Ghost. I really don't like her personality but I think she is actually really well written as a character, not likeable, but very much consistent and with a strong motivation.
Firstly she is just an ordinary gith, but being a gith at all is an oddity in this setting. She might as well be an alien, tons of the npcs don't even know what species she is. When you play as a gith, or initiate conversation as her, lots of npcs bring this up. If you check the wiki on githyanki not only are they rude and arrogant but they are also so dismissive of other species that they don't bother to learn their customs and languages. And she's an inexperienced gith. Her whole deal is she's a stranger in a strange land. She needs you. For the time being.
This is highlighted by the fact she is the only companion you meet in EA who actually needs rescuing before recruitment. Caught in a goblin trap of all things, by two tieflings she could carve through like butter. Even what the tieflings say about her, yellow as a toad and twice as ugly. Even if she could find it, they mightn't even let her in. She knows they've already met her people and it sounds like they didn't make a good impression.
You get a sense of what she thinks of you if you take the nice option with Zoru, she calls you a subordinate, because that what she thinks you are. But they specifically put in a line to answer your point about why she doesn't leave right there. They pretty much lampshade it. She mispronounces tieflings and if you comment on this, she demands you teach her about Faerun. She's got 13 int, and she knows she doesn't have a clue about the area and as such she needs you. But if you cast detect thoughts (or illithid power) either here or later you can tell that she already thinks of you as abominations. Most characters should maybe be considering that Laezel isn't so concerned about purifying us, as opposed to just her. You get the feeling Gale is harbouring doubts and Shadowheart doesn't trust her one bit.
At the mountain pass, she does something unique in the EA IIRC, she leaves the party, but not to go hostile. She just does her own thing and doesn't give a damn about us. I'm not sure, but at this point I really wouldn't be surprised if she got the okay for purification she would just abandon us and get them to kill us. Nothing suggests otherwise. Of course the nuances of a lot of this change depending on what choices you make and whether she dislikes or has a grudging respect for you.
I think you're right about the creche, but it would have been unfair to put in her leaving if that route wasn't available in EA. I hope for the sake of consistency if she does agree to go the other route it would be after a decently hard skill check.
Of course that's just her when she's used as a companion. She would probably have to be a bit more different as an MC. Again, that's one of the big cons of the origin system. Quite a few bits of this stuff would have to be changed at a character level. The goblin trap just wouldn't make sense, she couldn't be overruled with Zoru as a MC and you couldn't really lose control of her at the mountains and all those are fairly significant character moments when she's a companion.
