What grass seed to plant to establish yard

Good luck with seed without adaquate irrigation. Your best bet would be some type of bermuda and hope the St. Aug chokes it out.

rye grass is perfect for this, its cheap and easy to get, grows fast and as soon as it has a root base the regular grass attacks it and grows over it like its on steroids

in summer heat any leftover rye grass dies out

I also think I’d suggest bermudagrass and just make sure you cut the St Aug at the proper height, 3 to 3 1/2 inches, and fertilize it well, so that over time it crowds/shades out the Bermudagrass, just understand that can take up to several years.

Maybe one one of the Bermudagrass gurus can suggest a type/cultivar of Bermudagrass, the least aggressive, to consider - ronk and Gamecocks22 know a lot about Bermudagrass. Seems like you have a large area to deal with and it might as well look good while you wait for St Aug to displace it.

Centipede is hard to establish from seed - takes a long time and a lot on care and commitment on your part.

One can grow carpet grass from seed and it looks like St Augustine, but I honestly don’t have a clue as to how difficult it is to establish compared to Bermudagrass or Centipede.

Problem with the cool season grasses like rye or fescue is they are going to die when the temps hit 90 F. If it was the fall of the year, which is not, then those might be options for consideration.

Would another option be to purchase 1-2 additional pallets (or more) of St Aug and spread the squares out in a “checker” pattern? The sod surface area would be way more coverage than buying plugs.

Then you can water the areas really well and let the St Aug spread to the bare areas.

Could you use some top soil/sand mix to level it out?