You talk about "counterplay" but you have a champion that is 100% immune to slows all the time. Why?

Who is that? Kalista. Not only does she have the ability to autoattack WHILE moving, something that's generally the antithesis to an autoattack character. But she also has a stun and an oncommand slow; albeit you have to autoattack them or hit them with your q. The problem i have with the character is that she is completely immune to any slowing effect you put on her because her movement range with her passive is not relevant to her current movement speed, instead to her boot level. I cannot understand how a mechanic like this is considered "balanced." It makes worthless any engage potential because she can do damage WHILE running away, then turn around and kill you before you can even touch her.

The suggestion i have is that kalistas jump range is not just based on her boot level, (where early game she still would have a smaller jump range) but also based on her current movement speed. such that if someone applies a slow to her, it reduces her effective jump range. Not a completely crippling range decrease like (jump range is equal to the current movement speed %) but rather something that would force kalista to use Rend to escape instead of merely auto attacking away from someone.

I know there will be people out there that will say, "she has counterplay, hard CC". But that weakness is not nearly made up by the champion being immune to any movement speed slow placed on her. I also do realize that auto attack speed reductions also reduce her mobility.