I don't foresee Zilean & Lulu as a part of the mage update, but Karma. Since Zilean and Lulu always functioned better when paired with someone else, but with Karma, it's a whole different story. The funny part is Karma's rework was meant to give the niche of a champion who could go mid and do well, which means she's supposed to be offensive oriented but with utility to be good at bot too, but meta and changes has a funny way of letting things happen and so Karma is now support in the balance team's eyes.
Common things to answer...
- Is Karma healthy? No.
- Is she balanced? Yes.
- Is she in an okay spot? Yes & No.
- Could she use some fix? Yes.
The balance team doesn't want to touch Karma not because they think she's okay, but because no one has an idea of what to do with her, FeralPony has been very forthcoming with his answer when someone asked about Karma months ago. He generally thinks she's in an ok spot now, but Karma has always been in an ok spot, but what's really ok about her? What keeps her relevant now is Windspeaker's Blessing which brings her support efficiency to an improvement, but she's otherwise your same ol' boring Karma.
Main thing is that the team does not know what to do with her, and the culprit of it is her Mantra. Riot has been so obsessed with accentuating Mantra's identity that everything in Mantra is overtuned but still underwhelming, and her abilities are also lackluster. Because they wanted to put out that one charge, ultimate Mantra, it ended up putting Karma in a difficult spot. Rather than to accept that Mantra will play somewhat similar to Jayce's or Elise's R, which is to provide additional utility, dps/damage, they put everything in to Karma's R without knowing it would cost her everything.
Players generally don't play her mid because she doesn't have something, that's true. No amount of "play her mid, she's good" will ever save her from the embarrassment of being a failure at mid. She has always been strong early-mid game, but when late game came, no matter how well you do, your abilities are less impactful by then. That's what makes her balanced in a faulty way, you're expected to snowball hard with her and win game early or lose everything you owned at. That's not a very meaningful counterplay, by the way. It also answers about whether Karma is healthy, which is a no. No because it's harmful to herself and harmful to others, she's got a very funny power curve (google Gompertz Curve), While other AP Mids have an exponential curve as they scale in to late game, Karma's power curve remains static.
She's in an okay spot because she's not exactly causing trouble, but at the same time, it's not okay because she's been so static, not stable. She doesn't do well but she doesn't do bad, she's stationary at best.
So yes, she deserves some fix. Karma lacks a niche in Riot's eyes, but the players fill it up for her anyway, so Riot's comfortable with it because players are comfortable with it. But the bigger problem no one wants to agree on is that the balance team has no idea what to do with Karma because her Mantra is problematic, and that's why Karma's in such a static spot too. And saying "if you don't like her at mid, play her support" vice versa is not exactly a good solution, so is saying "Karma is fine now, because she can jungle, top, mid, bot all at the same time" .
What to suggest? I suggest removing all her crowd controls and amp up her utility, so she'll get good stuffs like aoe heal, speed, and more damage. Personally, I don't think her W fits her overall, I never understood why an enlightened champion has a dot soul damaging ability with a snare and self heal, it's so weird. Karma has always been portrayed as someone who suffers and enjoy along with her people, she should have something that accentuates that spiritual link.
TL;DR, Riot doesn't know what to do with Karma because Mantra is in the way, their comfort with her is another thing.