Kalista and Tristana need a little help!

In a short summary, I think Kalista and Tristana should have minor reworks.

Unrelated to the recent changes, both Kalista and Tristana have been struggling over many patches.

Would buffing them solve the problem?

I don't think it would, at least in Kalista's case. These champions seem to become a sort of overpowered resource when they're viable. Tristana may be able to be balanced with patient consideration. However, she'd need to be monitored with a close eye during every patch.

Should they be reworked?

Yes. Any point Kalista is strong, competitive teams instantly pick/ban her every game. Kalista is extremely powerful in the hands of a professional botlane. They can utilize her passive dashes, spear stacking, support synergy (the empowered auto and ultimate), and rend very well. She has high wave clear and also adds a powerful smite to the team. Plus, she gives her support an extra gap closer and knock up / escape with a large range. Tristana has a kit of everything: crowd control(a displacement), a gap closer/escape( twice the range of ezreal's flash that can also buffer against cc), wave clear (her passive and active E), AOE, and a very high range at late game.

How could they be reworked? What do you want to remain in their play-styles?

Kalista is a unique champion that stands out in a distinct way compared to other marksman. I think she needs to have that appearance. I particularly enjoy her ability to dash with every auto. It adds a new unique way to kite and I believe it's balanced by her short auto range. Yet, her auto range isn't ideal. Her rend has become iconic to her design; however, I feel it can be changed. Her ultimate is very unique and powerful. It can be toned down. The image of a Kalista ulting her ally is very bizarre. Tristana, I like for her all or nothing play style. I believe the right call was made when they gave her a jump reset. She's great at getting away with an assassination or failing at one. I think her W needs to stay, the buffering to cancel a Blitzcrank's hook is very useful, and the mobility it gives her adds to her assassination potential. Yet, it's range could be shortened. It's not always necessary to be able to W a large distance. I really enjoy her ultimate! It adds more outplay potential to her kit and is unique to her. Her E can be changed. It's become part of the champion and adds to her uniqueness, but isn't necessary. She seems to have been overpowered anytime she has a lead, partly from her massive wave clear and ability to deal extra damage to towers. Her passive is in an awkward state. I always enjoyed her scaling range, but I haven't found much enjoyment out of her current ranges. It hit her early game hard. Enemy supports and adcs are having a very easy time punishing her if she wants to kill minions during laning phase.

In conclusion, I hope Kalista and Tristana have minor reworks and are balanced.