What is wild onion and what does it look like? I can't find it in the database. I have a bulb weed that is invading here.
I am amazed you have garlic chives going feral on you. It is one of my favourite herbs and not exactly easy to cultivate here.
For weed control, I use native groundcovers and, surprisingly, apple mint has spread through out the garden and is a good groundcover too.
I also mulch with tree mulch that results from people keeping their land clean of trees here. I find it a double edged sword because I rely on the seed of natives coming through.
However, weeds can just take over in a flash if I don't keep at them. Sometimes I have no choice but to spray Roundup in some sections of the garden. I daydream so much, however, and spray wrong things.