On the problematic side, the cheap boric acid solution (pun!) will likely be the most used. And this will be bad.

1) Boric acid will kill any insect that ingests it.

2) If you leave rotting fruit out, every nectar lover will drink it. From experience, this will be at least 50% honeybees.

So yeah, it will crash native honeybee populations too. If you are curious and want to see how effective it would be, mix up some bait without the poison. After a few hours, enough for every bug to find it, sit next to it for ten minutes. Count bees vs mosquitoes, you'll probably be disappointed.