Russia was already using Iranian made cheap kamikaze drones, they just haven't been as cheap. The Iranian drones have a longer range and much larger payload.
I guess Ukraine can just send 5 or 6 of these for likely a smaller cost the iranian ones, which combined can do quite a bit of damage, and are harder to shoot dowm by air defence, just by virtue of the larger number. Of course, each has its uses.
Hobbyists have been building foam core planes for years. There is an interesting youtube channel that has made plenty, FliteTest. They have built models to drop pumpkins and watermelons, so they can be build to haul a bit of weight.
One of my personal favorites is the Thunderquak from Darkwing Duck.