I want to be entirely honest: I used to love Karma...... even into Season 7 and early 8.... until they destroyed Celerity (removing AP for move speed) and then Nimbus Cloak.
Why did I care so much about move speed items?
In the current meta, Karma just is proving impossible to do anything but Q and E. If you try to use W and go tanky, you generally are underperforming unless you are fulfilling a specific purpose: Putting a top lane behind 2-3 levels through early game poke (which doesn't even always result in kill income).
Celerity/Nimbus allowed you to use her as a juking offtank which replaced tankiness with mobility. Now..... her E mobility isn't near as useful, and her AP building is so weak it generally isn't useful for much other than RQ poking bot lane 4-5 times before lane phase ends.
Building pure tank proves to be poor at clearing waves, and isn't strong enough anymore to tank pursuers in large numbers. Mid/Late game, it just doesn't stop aggression. (Two champions can now negate tank Karma's W/building tank. It used to be able to tank 4-5 people and survive and scale fast enough to do so)
In other words, I no longer see her as an offtank. I no longer see her as a tank. I no longer see her as a viable mage. She's just .... weak in all areas and her win rate performance is now completely driven by her team's performance, not what SHE does.
Which sucks. She has new beautiful skins.