My tarp has survived multiple high winds and hail storms while backpacking in the rockies in late July through late August. It has collapsed on me twice, due to me not staking it down well, but that's twice in probably 40 storms and if I pitch it correctly, and stake it well, I've never had an issue. It has also still provided protection when it's collapsed because the majority of the stakes have held, so no real issues at all. Depending on the pitch you use, you need to be mindful of wind direction so the tarp doesn't become a sail.
For the insects, a bivy similar to the ti goat ptarmigan or raven is hard to beat in conjunction with the tarp.