The stairs are level as with all the walling in the basement. I feel like the builders just didn't poor level for some reason. I know the layout of the house changed during construction and wonder if they were going to run the furnace and water in there at first.
I guess I'll probably start on the other side of the basement. That shouldn't need much it's pretty level and just may need a little grinding / floor leveler to get it done.
I'm thinking DMX 1-step followed by engineered wood. I don't think I need to put down OSB between, so it should be pretty straight forward.