What do you think Viconia would do if she lost faith in Shar?
One of the more interesting things about Viconia in the original Baldur's Gate trilogy - ignoring what Larian did to her in BG3 - is that she's actually not the best fit for a Sharran Cleric if you're familiar with the tabletop game. And the game actually recognizes this; even her default ending shows that she ultimately comes to cross-purposes with the Cult of Shar, destroying a sect that she herself founded. And that's not even getting into the whole "Viconia can be persuaded to become True Neutral" angle, which would only deepen the divide between them. So, I'm curious; if Viconia did eventually realize that Shar was lying to her and exploiting her - that she was, in effect, unworthy of her faith, just as Lolth had proven before her - what do you think Viconia would do?
Obviously, this would result in Viconia losing her Clerical status and attendant magic. But I don't think Viconia would move on to a new patron deity - not without extraordinary circumstances. She's given herself with true and sincere devotion to two gods now, and both have proven unworthy of her faith. Why would she open her heart to a third? At the same time, after having wielded the powers of a cleric, I don't doubt she'd seek to master another form of mystical power - but this time, one that isn't dependent on subservience to a master. So I could see Viconia turning to arcane magic and becoming a Wizard instead. Or she might be inspired by the example of House Oblodra and turn her thoughts inward until she awakens the power of a Psionicist. Or even both paths. But that's just me.