Problem with Kalista is that there is no counterplay to her mobility. Even if you have your own mobility, she has it on a passive and will out "mobility" anyone else.
Picking a melee champion that uses movement speed to catch their targets that at one time could still work, are just impossible to use right now vs her. In general, MS buffs should out preform dashes/teleports in the long run. But Kalista does not fill this. If you're looking for distance Ghost will get you further than Flash.
When Kassadin was at a 90% ban rate his existence pushed almost all immobile mages out of the game. Kalistia is doing the same thing. But it's OK because you're not supposed to chase her?
No one should be impossible to catch like that. Even Kassadin had to pay for his mobility. He couldn't do it forever. And he couldn't continue to attack while doing it unless he used it to close a gap. He's melee and his ranged damage is limited by cooldowns.
And how do you figure Kalista is not meant to be chased? ADC's are always a high priority target. Signed is rarely a high priority target.
- Put a cap on her E on monsters.
- Remove the bonus range when dashing backwards on her passive
- Lower the slow on her E.
If too much she can get buffs in other places.
- Increase range on passive when dashing after using her Q.
- Champions spotted by her W gain double Rend stacks.
- After her ally lands R, she gains increased passive range when dashing tward them
- Gains increased range dashing to linked ally. This could also just replace the increased range when going backwards. Meaning if you linked to a tank you're likely not going to kite as well. But if you're with say a Nami, if they can manage to stay behind you, you can kite better. Although this can make the skill even more technical than it already is and may be too much.