Giving Rionna a chance:
What I understand this argument to actually mean is this: people making it think that if we let her go and put in a bunch of effort, we can convince her agree to the things we want without bloodshed.
First off, I want to say that I think the way this is being delivered is honestly pretty disingenuous, because what I'm seeing written on it amounts to "we might be able to accomplish this and we should try." There's no accounting of the complications involved or the difficulties or the risks. Nobody is suggesting a real plan for pursuing it beyond "let's try to talk with her on even ground and see what we can do."
And yet, there are clear complexities involved in it that we can already see, and which everyone suggesting it is ignoring.
Example: one of the key things we can basically assume Rionna won't budge on quickly, if at all, is the topic of her sister's killer's shade. She is, presumably, engaged in doing unnecessary harm to that shade/soul -- given all the "I raised her shade" and "I hate her" bits, I think she clearly *wants* to do that.
But nobody is mentioning the difficulty of getting her to give that up, only how we should talk with her on even ground.
The real question is, is there something we could do that she would agree to give up the shades and stop murdering for? And in part that has been answered -- she wants her sister back.
What isn't answered is whether or not she'd give up her shades -- including that of the killer -- for her sister. And, for that matter, whether she'd cooperate with us is also unanswered.
The only thing I've imagined which could bring back her sister would be a wish, because presumably she doesn't have her sister's shade, or she'd be trying to bring it back to life -- or so you'd think.
But suggesting a wish to her... There's little reason for her to give up what she has before or after hearing that suggestion. From what I've seen of her I don't think we can trust any deal with her around that.
Anybody saying we should "give her a chance" needs to first lay out a coherent plan for how to do that *and also how we should expect it will yield some result except her being a much tougher opponent.*