Can you recommend an effective weed spray that's less toxic than Round-Up?

Don’t be afraid of roundup. Just make sure you shower right after you apply it, wear clothing that covers your skin and just do what you can to not get it on you. I’m sorry, there is no magic organic bullet. Alternatives usually are acid and iron based and will affect soil. Roundup will kill the vegetation without damaging your soil. Roundup will also kill what you apply it on while sparing what you don’t. I’m not for using it on crops we grow for consumption but, it works wonders around the yard.

There are two natural ways of doing it. Vinegar and salt, but keep in mind it will make the soil useless. But boiling water can also kill it down to the roots without ruining the soil or anything nearby if you are careful in pouring it.
Another method. One that I use is pouring a lot of water or waiting for a heavy rain to pull out the weeds by their roots with a weed puller.
I never liked round up because of two things. It ends up in our water system and you never know what animal may come in contact with it and get sick or die. Especially pets.