1. Karma is a high skill floor, high skill ceiling champion.
She has one ability has a shitty hit box and very short range. Making her Q useful depends on a long cooldown, hitting the regular shitty q for cd, and staying in range and trading for cd. In addition, all of her abilities depend on empowerment to be useful.
2. She has the most difficult "in the moment" decision making when it comes to having to chose which ability she wants to be useful.
3. She is the most interactive champion in the game. She is the only champ who's kit is designed on constant interaction with the enemy to make her kit work. This gives her massive counter play no matter what champion you are playing. Literally every champion is her counter. She also has massive interactions with her teamates
4. She has to take massive risks to make her kit work. The thether works in a way that makes her be in danger for an actual reward.
She needs buffs to her q, w, and e in order for her to not be a total dumpster fire. If she had these buffs she would be the definition of a fair and healthy champion. If not a model for how new champions should be modeled.