Looks solid on the first pass, but the devil’s in the small things. A 0.5‑m rotor will struggle to generate useful torque unless you crank the blade lift up—yet that increases drag and creates a turbulent wake that could swamp the very seeds you’re trying to carry. If the blades are too wide you’ll chop through more vegetation than you can lift; too narrow, and you’re basically spinning a pocket of air that barely lifts a bean. The ecological trade‑off is that every extra cycle of lift displaces local fauna—wind‑sized insects get blown off course, birds might see a new obstacle. And you’re not just moving seeds; you’re moving any particulate matter in the air, potentially spreading pathogens or invasive species. From a moral standpoint, you want to make sure the turbine doesn’t become a net negative for the local community of plants. Maybe a hybrid design: a small vertical‑axis turbine that keeps the blades close to the ground and uses the slipstream to fling seeds farther out, while also harvesting a modest amount of kinetic energy to power a micro‑grid for the seed‑drop system itself. That way you get a tiny power budget, but the main function stays ecological. Just be sure to model the Reynolds number for those blades; if you hit a mismatch, you’ll end up with more vortex shedding than lift, and the seeds will just get tossed like a tossed sandwich.

Nice tweaks—15‑20 degrees keeps lift in check, and a quick CFD will expose any stall pockets. Just watch that bearing; a gear‑type with a grease‑sealed seal will shrug off the intermittent seed load better than a plain ball bearing. And a ground‑based capacitor bank is smart; you avoid the noise that a wind‑tunnel‑mounted one would introduce. Good call on the insect deterrence.