I had disdain for Kalista back when Runaans was first run on her and she became game breakingly busted for months until it trickled down into lower elos. But fast forward to today there are better picks at this point unless you are a professional Kalista player and have a professional support too maybe she becomes viable then.
Part of the Kalista problem has always been her build IMO. It was ludicrous she is expected to do sufficient aoe on-hit damage using builds more defensive and cheaper than crit. In fact crit is almost anti-synergistic with her (but not necessarily useless tho) as such a build reduces number of hits to kill reducing her on kit power. On the other hand, her on-hit spears ARE pretty cool... but maybe she would be more balanced if she needed a build that didn't constantly increase her kiting and tankiness. Crit = double spear stack is an idea if awkward example.
Kalista became a lot "easier" when people started building 
on her. Before that you at least have to focus and stick to a single target while manipulating her jumps, but with that item her playstyle becomes "orbwalk away auto'ing incessantly". Riot probably isn't found of making Kalista an even more difficult champion however. She's both difficult and annoying as heck... how to bring her together....
People who play against her want to get rid of her jump. I don't think that's likely. (I just can't see her auto'ing without jumping at this point) Riot sees her as the teamwork soulbinding champion. That's ok too imo, but average players don't see her that way as they don't trust their solo queue randoms. Another unique high she has going for her is her rend and spear stacking. I think if this was gone while we'll lose those glorious executes the rest of her gameplay could be the focus and her build could be more standard and spike mid game less hard. She is a very unique champion without the on hit build going on already.
