Parachutes! Nice one Kostas!
Have been looking at drones aswell, but more as a tool for dispersal, definitely worth looking into.
What i've been wondering is if using a weight, maybe a clay disk, on the bottom of the bag, on top several smaller seedballs, packed tightly, whereby on impact the bag would burst, dispersing the seedballs over a larger area.
The clay disk could contain other beneficial stuff, and/or small seeds.
But i figure a picture is worth a thousand words, so prepare to be amazed by my awesome sketching skills