They say that if you have dragonflies around, the ecology isn't compromised. So today, this mosquito-eating monster landed on my balcony and peacefully napped on the wall, hiding from the ever-present
swallows that have made nests on the balconies and in the underground garage of our building. Does that mean our ecology is all good?

Actually, dragonflies' presence is a good indicator of a balanced ecosystem, but it's not a definitive measure. You should also consider other factors like water quality, air pollution, and biodiversity.