I don't understand why everyone hates her design, because of her Passive the rest of her abilities are very limited.
R isn't a damage based ability, W isn't a damage based ability, Q is just a basic skillshot ability, and in order for E to deal damage she needs to apply enough spears on the enemy, which requires a lot of Attack Speed. All of her damage is centered around her E and she's one of the few Marksman who don't crit for a billion damage (Draven, Caitlyn, Jhin, MF, and practically almost any other Marksman).
If the problem is that Melee's can't fight Kalista then you have to deal with it, it's basically the same as being unhappy that you as a Zed can't lane against a Swain for example. There is a thing called counterpicks and it's something that Riot will most likely not going to remove. You can just CC chain her and she becomes as useless as any other Marksman.
Every champion has it's pros and cons. For me as Varus I have to deal with the fact that I can't fight champions like Yasuo, Irelia or any other mobile champion even with all the CC that I have (E Slow, R CC), because they have mobility that helps them get out of tricky situations and better damage than me even if my champion is considered a Carry.