why are you trying to hit 1000 grains? that is near 18 grains per pound, I like a heavy arrow too, but usually ball park it around 9-11 grains per pound.
I have shot maple, cedar, fir, hickory, chundoo and sitka spruce. all have wonderful characteristics. I love cedar mostly for the associated history. hickory made great squirrel arrows. Chundoo took a good beating while stumping. Fir and sitka are the best all around for me. good variety of spines and weight available, easy to straighten and stay straight.
70-75 spine sounds like a good starting point. I prefer bareshafting into a soft target from 15 yards or so and watch the arrow in flight rather that reading the tail after impact.
I like to shoot a rear tapered shaft and soak them in watco oil for a week or so before fletching