1. Mechanical instead of chemical for the weeds. 2. Choose the right soil instead of "adjusting" an unsuitable soil with fertilizer. 3. I have had very good experience with EM in the garden.
We had proper soil delivered, that is, a topsoil substrate for lawns. First year okay, second year full of weeds. They grow faster than grass. At least 1 hour every week pulling weeds, leaving holes in the lawn. We also have children. Then applied Compo weed free, of course before a rain shower at the beginning of the season. That is enough for a year without weeds. Eventually the grass is so dense that it almost fights everything by itself.