I used to try to vary brace height as part of tuning the bow to the arrow. Now, I do it the other way around.
After spending some time getting a set of arrows flying the way I wanted them, I was amazed to see the difference that a small change in brace height made: just a couple twists tighter and the arrows were looking limber. (I had a chance to shoot them over a chronograph and found I was losing a few fps -- more than I would have guessed!)
I use dacron strings and have come to believe that temperature makes a big difference in brace height. So I now always string my bow, twisting or untwisting as necessary, to "one fistmele" - a measurement I can always reproduce. When making new arrows, I putz with the arrows until they're right at that brace height.
YMMV.