Karma's Passive should get the same treatment as new Taric's passive
As in, lower the base cooldown of mantra (40/35/30/25?), but make the cooldown refund lower when you have higher CDR.
This would mean she'll be better with a lower amount of CDR but still the same with higher CDR (which she typically rushes these days anyway).
Note that this isn't necessarily a buff in her main roles (aside from possibly waveclearing) -- it just means that not building CDR won't be completely terrible on her any more. Would make her a better jungler too (since her passive isn't utilised much).
... Otherwise, I think the RE buffs need reverting and her RW buffed instead. Then she'll be in a really good spot. RE's just too strong at the moment and RW is really overshadowed to the point where it's too situational to be a core ability. Ideally, her 3 mantra spells should be equally useful in general. It makes her decision making matter more. Perhaps RW could also make the enemy grounded while leashed (unable to use movement abilities).