Glad you figured out the gimmick! (As a non-American, I too had only a vague idea of the specific state abbreviations in the NYT crossword.) I decided that since Thursdays are the hardest day of the week with a gimmick, I'd err on the harder side. Make sure you check those clues!
I considered making the maths in the 12A12AWorkforce required to build N walls in N days, assuming it takes a man N days to build a wall[---] clue a bit trickier, but figured the fill was weird enough. I was inspired by "A manager is someone who thinks that 9 women can deliver 1 baby in 1 month."