Yep, Wyll is in the grove and definitely favours defending the weak … usually.
I agree with folk who say Shadowheart is a really useful party member. She can buff & heal, do reasonable spell damage, use a crossbow or even melee weapon in a pinch, really help your party with stealth, and open locks and disable traps given her Urchin sleight of hand proficiency.
She’ll grumble a bit if you go out of your way to be helpful, but generally (as an urchin background) favours helping the underdog and even reluctantly comes round to a level of do-gooding. If you take her at face value, help her out on the nautiloid, and don’t pester her for info she’s not ready to give, she comes across as friendly and appreciative and to me it can really feel in the course of early access that we’re laying the foundations of a real friendship. There is also reason to worry that we shouldn’t take her at face value and she is possibly cosying up to us and manipulating us for her own ends, but for the bit of the game we have I think she works perfectly well in a good party that’s at least minimally tolerant of different views.