First stuffs that must be stated. There is nothing that doth not involve moving another player that will ever be a better option. No matter what changes someone suggests we will lose something we had the ability to do and the versatility that accompanies it.
Imagine you are playing hmm, Starcraft 2 (have been playing this with the family much lately so tis on the mind). There is ability cast by motherships in there that creates black holes that suck up all the things. You can use this to protect allied units, disable enemy units, or even for setting up wombo combos. Now let us say we agree this is op as all heck! Tis primarily used to protect allied units soooooo replace with temp invuln shield. Alrighty! Now I have turned a highly powerful and versatile utility skill into binary boring box standard unit invuln. You cannot have one thing without the other.
Sucking up units has far more uses then giving units invuln even if it can be utilized as invuln. Invuln is binary thus used only to protect units that would parish or take damage without it. Phew! Had to say this because it is important to a Mia.
When we inevitably lose Rescue and let us face this we will. Am surprised we have been allowed the keeping of it for so so long already. Square hates anything non restrictive. Everything is make hp bar go down - raise allied hp bars - reduce damage by percent - etc. Easier to balance so there is understanding but I do not have to ficken like it. Your solution is the most likely one.
One; Reactive raise already exists within codebase in form of Pomander of Raising.
Two; Code for reactive skills already exists, think Excog.
Three; Prevent going below 1 hp code also already exists.
Slap all three together and you have reactive raise. We will not get reactive telewarp though because developing that would require additional time. Am willing to make wager on this can quote this Lala if I am correct in the future times. Heck number three is not relevant so can scrap that if we go with boring ol auto raise.
Now finally.. many apologies I kinda type a lot. Your suggestion is mostly dumpstered on arrival.
In higher level content (Savage+) and even most lower level content skilled players avoid anything that has potential to cost uptime/deeps. Just like avoiding old pre dps neutral Lily spells a skill that causes someone to eat 40% damage down will be avoided as much as can be. Whole reason why rescue = better is from its ability to prevent the weakness debuff and uptime loss of raising for both dead player and healer. Damage down portion has to go or be augmented or the skill goes from "Sweet! It worked!" to "Ugh, guess I will slap this on them instead of burning Swift".
How does it slingshot the player?
If it works as current Rescue does will it move player to current position or previous position upon cast?
Both have potential to be most bad. I identify that player A is not going to survive mechanics and shall experience demise. Wish to use Conditional Salvation on them but it will yeet them to me however there is kill wall/chasm between me and player A. Gotta reposition before casting or make certain I do not reposition until they experience demise which miiiight result in my going splat. It will have to function like raise so again we return to reactive raise.
Most biggest reason why it would insta flop especially in higher level content is how fricken punishing being out of position is there. One player not correctly positioned in Dragonsong Reprise results in tpk 95% of the times. If it becomes reactive raise without the yeet portion welp.. now the dead player is not in position for mechanic X so wipe time! If it retains the yeet but you must position for mechanics now you are dragging someone somewhere they should not be and that is a wipe again.
All of this is mostly irrelevant in casual content but thought twas worth the mention because current Rescue has value in both casual and high level content where this new skill would not.
In a world where Rescue must go bye bye I instead propose that it be replaced by reactive raise or interrupt with additional conditions;
Square ceases using the restrictive moniker Healer and switches the role to being called Support. Prevention is key part of being doctor after all! It is most important part actually especially when the alternative is surgery. They must stop viewing healers in this binary, restrictive, bland way they do as resource to make the hp bars go up or prevent them from going down as much. It is.. dreadfully boring. Despite this being easiest thing to balance around they are not even very good at it.
Just look at the new Ultimate! No room for triage there. Everything is insta kill so only healing needed is so scripted you could use third party tools to call it out or push the buttons for you. If this is future direction we are stuck proceeding in then we do not need more heal buttons or raise buttons.
What we need are more skills like Rescue and Expedient. That is final stipulation for me! Remove three+ heal buttons from every healer and replace them with unique skills similar to Expedient. Something beyond |Reduces damage by %| or |Heals by X amount of potency|.
If they do this I would begrudgingly accept the removal of my Rescue. No no they do not have to move someone like Rescue just.. be anything other then another mit/shield/hp go up button. Anything is more unique then that. I want support closer to Lucio from Overwatch (He was my favorite! Will shill for Lucio).