I do loathe mosquitoes and yellow jackets (and all wasps/bees). Despite only having a few instances of encountering cockroaches, those also still disgust me. However, as much as I would like all of those creatures to no longer exist, I do understand that they serve a purpose and them ceasing to exist would be very, very bad for us. Disrupting the food chain by wiping out any one or all of those would have seriously negative repercussions. Butterfly and Domino Effects. Everything is affected in some way by everything else. Eradication isn't needed to completely fuck things up. Simply disrupting things just a bit can be enough to result in big changes; e.g. the effects the proliferation of frequencies used for communications have had on the honeybee populations around the world and the resulting effects on pollination and agriculture. No more mosquitoes and the creatures that rely on them as a food source to exist go away or adapt to eating other creatures. Just few adjustments to the food chain and before you know it we're in the stone age. - Pollination becomes disrupted enough and there is no more agriculture and human food sources are adjusted to other sources. - Disrupted agriculture also means no feed for cows and other animals that we consume, resulting in human food sources further adjusting to other creatures. - Bird populations and migrations are disrupted with the result being, among other effects, that the animals that feed on birds are also disrupted and they in turn adapt to alternate food sources or die out. Wipe out the mosquito and, given enough time, the effects could potentially result in the wiping out of much of life on the planet, and particularly humanity, as well as fundamentally alter existence for any life that still remains in the new dynamic of existence that forms. There is only one creature on this planet I can think of where its complete eradication would only result in positive effects on the world in every possible regard.