Different nests can be as close as a few meters and their inhabitants will mostly ignore each other. The hornets were about 7 or 8 meters away from the yellow jackets, and I have never seen them fight. If you put some fruit or honey somewhere, they will (mostly) peacefully share it.
European hornets are not aggressive at all, they are just big and loud. When one gets into the house, I usually wait for it to settle down somewhere and then carefully catch it with a glass and a piece of cardboard. We also have mosquito nets on all windows and doors.
Another fun fact: wasps will not spend much time around their nests. They usually leave the nest at high speed (do not stand there!) and then roam an area of multiple square kilometers. When they come back they immediately go back into the nest. Sometimes a single animal may inspect the closer area, but this is rare.
Once you understand wasps, there is not much to fear. I understand your concerns regarding you child/children, and it is probably a good idea to keep wasps at a distance for some time. When children grow up, there is little danger, though. The sting of a single wasp or hornet will not harm a human being unless you are allergic. (European!) hornets use almost the same venom as yellow jackets, only more of it. (In Asia or South America, be more careful!)
Finally, wasps do not want to sting you. Most of the time they are just investigating. When a flying wasp bothers you, slowly and carefully push it away with your hand. Most of the time it will just go away. On the net there are videos of some guy who tries to get stung by various wasps. It is educating to see how much he had to bother them before they did.
My experience of sitting outside in the summer (modulo NW England) is that their flight path covers getting close to 100% of the airspace in my garden.
Though I'm sure there are other varieties I've only ever seen one type of wasp in the UK, and that's this one https://en.wikipedia.org/wiki/Yellowjacket, and my experience of them is that they are irritating and aggressive bastards. I don't doubt that wasps are an integral part of the ecosystem, but I'd prefer it if they integrated into a geographically distinct part of the ecosystem from me and my lunch.
Having been chased by wasps while on a riding lawnmower, I'm calling bullshit! And those suckers are fast!
Seems like you are talking about bombus, not vespa. The worst thing about hornets is that if one insect has bit you somewhere near their nest than you better run as fast as possible from that place because of pheromone mark.
Not the wasps here. There's always a few wasps flying around the nests when I find them.
It also doesn't take much to aggravate them.
But to answer your question more directly: We have happily surrendered part of our terrace to wasps. Their right to live tops our desire for convenience. A nest lives for one year. If we do not want them to use the same spot next year, there are ways to make sure they do not.
I can intellectually process all the facts you wrote, but in my dealing with wasps and hornets, I find it hard to see them as anything than fast-moving balls of pain, always ready to strike at you out of nowhere, when you least expect them. Also, as a relatively fresh parent, as a threat to my children. I tend to prefer dealing with them by installing mosquito nets in all windows, but if a hornet gets in and doesn't politely leave, it's makeshift flamethrower time.