Thanks for the input on spokes.
Not too concerned about the weight difference between the brass and aluminum. We are talking a difference of 20 grams per wheel.
I found the DT calculator. Only thing I am not 100% sure about is the correct ERD for the rims, as Easton uses ERD++. Don't think it will make much of a difference, as the spoke length is the same if the ERD is between 583-584 (meaning the nipple height is between 1.5mm and 2mm).