While bee and wasp stings are painful, horse fly bites are worse IMO as they become inflamed and sometimes get infected. I saw a false widow spider in our garden last year. Didn't get bitten. They're definitely not deadly but I've read their bite variously described as like a wasp sting to excruciating. We go to Scotland a few times a year as my son lives there but so far haven't been bothered by midges despite sending a lot of time in the countryside. They do appear to be a real menace though. We're quite lucky in this country to have so few creatures which can do us harm. I always check my legs for ticks these days if we've been walking in long grass etc. Not sure if they're more common these days but I was only vaguely aware if them when younger.