Generally I am fine with a redemption and/or corruption arcs. WHEN LIMITED to a very few charecters. I think Sarevock’s was done well but Viconia’s was not. I am honestly looking forward to what appears to be planned for Shadowheart; however, I hope these are not going to be a theme. Astarion needs to stay is snarky self but build confidence, Gale needs to find balance in his self, and the “Blade of Frontiers” needs to put up or shut up
. But a true alignment change needs to be supported by good plot points not by romancing, etc.
I love redemption stories. On Viconia, her redemption fell victim to corporate shenanigans. WotC had moved onto 3rd edition, the infinity engine was not well suited to 3e and so the story was quickly brought to a close in Throne of Bhaal. A forum member - who went on to write some mods - Kalthorine ut Wistan came up an outline for a Viconia redemption arc -- David Gaider, the ToB project manager agreed that it was good and all but admitted that it would been better than what he himself came up with but said that there wasn't enough time in the game to implement it.
Viconia should have fallen from Grace and charname left with the difficult decision to bring her back into Shar's good favor (ending the romance) or accepting Viconia as a companion who couldn't cast spells (excepting scrolls) for a prolonged period of time.
It fit with her story - she left Lloth after a crisis of conscience and Shar granted Viconia power at her weakest moment. To become good Viconia would need to learn to stand on her own without the aid of any deity.
By the end of BG2 the romanced Viconia is completely at odds with Shar's teachings - she's sharing secrets with her lover and reeling in moments of joy instead of nursing a resentful bitterness. Shar doesn't want her followers to recover from past pains. Instead, old wrongs are to be remembered but never revealed to anyone but Shar -- the only respite from pain comes from the forgetfulness that will come with joining Shar's infinite darkness. Old wrongs will only righted when everything existing is destroyed.
TL;DR, I don't think the redemption story in the BG2 portion of the game was bad at all, it only falls down in the ToB DLC section. But that wasn't Gaider's fault - Bioware and WotC screwed the fans.
Edit: As the red queen says, it doesn't make much sense to have Vicky in the party if you aren't romancing her. But then that leaves you will Anomen as a healer - I usually use a mod to lift romance restrictions.
