Slings

Slings would be a way to put back the hold down projectiles from way back in the days of Minecraft. Craftable with leather and string. Cobblestone can be crafted into sling stones with three per cobble. The catch is that these stones only do as much damage as a punch, although they are enchantable with power increasing the damage given.

But the slings real utility is in the second projectile I'm proposing, Glowballs! Take a slimeball and glowstone dust to get a glowball a projectile that when thrown at the ground will create a carpet/snow like layer on one block that will act like a light source equivalent to a torch. It can be washed away because it is just slime soo its not too op. This will help in lighting up the huge new caves in 1.17, as I imagine now that one torch doesn't light up all the spawn-able area around a player like in the old caves, the gameplay flow is a little slower and more monotonous. Slings with Glowballs make it to where a player will only have to stand in one spot to light up a very large room, and considering it requires mid game materials to make and post game farms to mass produce the balance should be fine.