Mmm, so the vote is kinda interesting because on the surface it's a "safe vs. risky" vote.
But that's purely from gameplay/ic-decision standpoint. Historically, us getting too hung up on trying to be proper and make the "sensible" decision hasn't always led to the best outcomes.
If we look at things from a narrative engagement point of view, the big thing that the formal vote offers is honestly the spar. Being all professional and everyone just doing their jobs and not engaging more deeply means we're less likely to get a strong look at Xia Lin's character and personality. This means we're less likely to get as engaged with her. Similarly, focusing on talking about the mission and expectations will probably not be wildly satisfying since that's just going to be redundent with what we have to do with Renxiang later
anyway, so it probably won't do much here. The spar is the main thing of interest, and that's mostly with regards to seeing how Xia Lin fights, as we haven't really gotten anything new since our last fights on screen.
Friendly otoh, while seeming risky from a gameplay standpoint is actually great from a narrative one. It's more focused on getting to know her more as a person, which is great for making her a character that we're interested in and want to see more of. It's more social focused which fits the challenges of the current arc more than fighting. And even if things do go south, that just means we've now got character conflict which is narrative fuel! If you think of it like that, we can't lose!
More seriously though, people have talked about how being formal might be more comfortable at the start, and help getting to know her better later on - but isn't that kind of just treading water? Moreover, the focus of vote 1 as described isn't to be formal and polite as a way of getting to know her better in a way she might be more comfortable with - but rather avoids trying to get to know her by instead focusing on talking about work and things.
So you know what? I'm willing to roll those dice.
[X] Be friendly, show her around and introduce her to your spirits. They will be members of the party too.