Players should consent to Kalista's spear!
Honestly never liked the whole "click on champion to bond them to you for an entire game" mechanic. How long does a Thresh lantern, a Bard ult, an Anivia ult, and so on last? Something as permanent as that should be consensual (just like real life relationships!).
Right now, it can be abused by dumb Kalistas spearing you in lane or in the jungle when enemies are around. Free damage for the enemy, I guess.
If it was consensual, it could show a thing or two. People could decide whether or not they want the spear: the jungler for better ganks, or the support for better poke. Supports that don't poke a lot might decide it's better for the jungler, and so on.
The only con of making it 100% consensual is that sometimes people just don't want to be Kalista's bitch partner for the entire game. That should say something about her design, Riot. It really does say something.
Sona, I know you're squishy, but I promise to only use my passive to compliment your pokes and my ultimate to save you.
...
Make out already!