I have just thought of something. Since there are less healers, we need a new healers and also a new twist kind of healer.
Can you create a hero where he/she can summon a spy (that can disguise as an hero of the opponent)
but this spy will be placed in the area of opponent.
Now, about this spy, it can heal your team by shooting at your own heroes (instead of giving damage, it gives health) and when it passes by the opponent’s hero, it deals damage (like an act of assassinating). The healing rate would be equal to Nightingale’s Heal Pulse healing rate but per hit, per heal. If head shot then greater heal. Like an healing gun.
And of course, opponent’s AI can’t detect this since it’s a spy (it sees it as ally). Only the player-controlled hero can know and hit it.