Along with other commenters here, I've given up on trying to have a perfect lawn. As long as it's green, it's fine with me. I'm also trying to gradually reduce the amount of property given over to lawn by a little bit each year as I expand beds of native plants. In my experience here in the Mid-Atlantic region the upkeep in terms of time between a lawn and garden bed is pretty much a 1:1 tradeoff. Occasional weeding and a one-time day spent planting annuals in the Spring is about the same as having to mow every 1.5 weeks.
My lawn definitely has it's share of crabgrass which I don't mind. But Kentucky blue grass and clover (both native) seem to do better. Which unfortunately means mowing.
Crabgrass also gets tall (it grows faster than my bermudagrass) and will die back at the first frost. In comparison, Zoysia and Bermuda will go dormant but maintain a ground cover to prevent erosion.
