tldr - Yes, Ahri is not as dark as she used to be. But that was a static situation for her. I like that she now has a more in depth history and much more potential for future growth, discovery and interaction, while still offering an occasional glimpse of her dark side.
I'm not sure the status of Ahri's seductive-cunning side is that different. In her new background bio, we go from...
1 - 'Ahri living with foxes' to
2 - 'Ahri happily devouring souls' to
3 - 'Ahri regretting her destructive nature' to
4 - 'Ahri determined to find a way to deal with it'.
It fits pretty well into a narrative arc that ends at the story's midpoint. Garden of Forgetting would be somewhere in 3, the story with the fortune teller is somewhere in 4 or later.
In her old lore, she went from...
1 - 'Ahri the fox turned human-ish via magic' to
2 - 'Ahri seeking souls to complete or maintain the transformation' to
3 - 'Ahri realizing "wait, I shouldn't be doing this" ' to
4 - 'Ahri going to the IoW and asking "hey, can I fight here to get the souls I need? k, thanks" and joining the LoL'.
So even in her old lore, the cunning, seductive, questionably-evil-ish Ahri was still just a stage in her past, as it is in the new lore. The difference is that in the old lore, joining the LoL gave Ahri an excuse to continue doing what she did, just within the confines of the LoL and without the negative consequences (IIRC, mages or something were researching how to address her condition). There wasn't much more to progress with her storyline.
Now she doesn't have the crutch of the LoL, and needs to find a way to address her addiction on her own. And I think that how she goes about solving this problem will provide ample opportunities for the cunning-seductive Ahri to return when she needs it to, along with interesting internal conflicts. Say Ahri finds a priest or tradesmen that knows something of the talisman she carries, but refuses to tell her. Does Ahri resort to her abilities to extract the memory from the person? What if he has a counterspell that prevents it? What if the memory is buried so deep, Ahri would need to kill the person in the process? The new lore implies that Ahri has an ability to siphon people's energy or whatever to keep herself sustained without killing them, but how long can that last? With an addiction, she'd reach a tolerance point eventually. She could relapse and wipe out an entire village again, as mentioned in her new lore (cue "Monster" by Imagine Dragons). And she might not even find a cure - her resolution could just be learning to accept - or even embrace - the fact that she kills people occasionally. She could learn something about her past that would lead her to, as you say, think less of the people she kills. Siding with Xayah would certainly give justification for not caring about human victims.
Plus, who is to say that she doesn't still enjoy occasional games and mischief? I could see her in a tavern, toying with the emotions of a young couple nearby on their first date, for her own amusement. Or showing up at a wedding and charming the groom, just to cause trouble. She's just not trying to kill anyone this time. (Kind of like Jinx, but more for drama than explosions, and turned down to about 3.)
So, I think there's still room for the cunning-seductive Ahri, it's just not her entire character anymore. When you read the fortune-teller story, did you envision Ahri in the red dress from her splash art? I didn't. Redemption could be part of it, but her goal seems more of self discovery: 'who am I, where did I come from, and how do I stop doing this' rather than 'I killed all those people and need to make up for it'.
My guess is we'll see more when we get the Noxus invasion of Ionia. For one, it might actually give us a chance to see Ahri interact with other champions and factions. We can come to certain conclusions about Garen because he's from Demacia, or about Ashe because she's from the Freljord. We don't have that luxury with Ahri, because she's not really associated with anyone. I'd like to see her put in a position where she's forced to take a side. The Noxus invasion would also give Ahri a chance to use her 'skills' to either help people in need, or willingly aid Noxus in return for info about her talisman. (I would love to see Ahri end up siding with Noxus, even if just for a while. Given her past, she's probably made a few enemies in Ionia - taking out a whole village likely wouldn't go unnoticed.)
All that said, there's one point in the new lore I'm not entirely satisfied with. If Ahri is indeed as old as several human generations, as the Piltover explorer's story suggests, and she has been collecting memories for even part of that time, how is she not some beacon of historical knowledge? If she's clever, how has she not put together all the various pieces of memories she has collected to come to some important realization about... anything?
It's implied that Ahri has seen a lot in the memories she has collected. If I'm understanding it right, it's as though she's a walking Wikipedia History section. So, what happens when someone important in Runeterra realizes this? Surely Piltover or Noxus would want access to such a record? Would they go after Ahri for her memories, or for her abilities? Could someone realize she holds memories that they would prefer to be forgotten and try to kill her? Would anyone come to her defense?
And where does Ahri get this ability? If it's from the talisman, are there other 'walking Wikipedia' people on Runeterra who have similar talismans? Maybe a subtle reincarnation of the League of Legends, collecting information about Runeterra? Alternately, if this is a racial ability from Ahri's branch of Vastaya, how is this species not in powerful positions in Ionia or elsewhere? Were they considered a threat and hunted, perhaps explaining why Ahri was abandoned in the snow?
^ And this is my favorite thing about the new Ahri lore. She's not just going around seducing people and consuming souls (though I certainly liked that, too). The fact that Ahri retains memories, and has a motivation to learn more about her abilities and past sets her up to potentially be a really, really interesting character.
. Oh well, there goes my AhrixWukong shipping...
