1. The short range is a killer. You already need to know where the bad guys are, within an area of a few blocks. And solar panels with such small form factor are a joke in comparison with the energy demands of powered flight. (Sure, there are solar powered drones, but they need huge wings, perfect weather, and are little more than powered gliders.)

2. I didn't see any good counter-arguments there. Care to detail.

3. Explosions will alert the building's occupants, and you just sacrificed a complex, expensive device for a $0.50 mosquito net.