Overseeding a sunny Michigan lawn, best seed?
I am looking to overseed my ~3500 sq ft lawn shortly, and would like some advice on the best choice of seed, and even brands. I am in southwest Michigan and my lawn is currently dormant. I'm not sure what type of grass it is, but it has shallow roots and lots of thatch, despite dethatching this spring. I heard the previous owner had sod put down a couple years ago. The soil is very hard in most places, and is mostly full sun. All of the grass is brown, except for a nice green area by the privacy fence (I am assuming the previous owner used a shade grass, but the only shade is a two foot shadow next to a fence). A good amount of weeds have crept in, and there are quite a few bare spots that weren't there last fall.
I am looking for a good seed that can fill in the bare spots, thicken any thin spots, and hopefully crowd out the weeds. Ideally it would have a deeper root system that what is currently there (Beyond Scotts and store brands, I'm not familiar with seed brands, so I would certainly like to hear any recommendations on brands to look into.