You could split the difference and go with an aluminum/carbon arrow.The Full Metal Jacket 300 weighs 11.6 gr per inch. and packs quite a punch.You coud shoot that at 70# and keep all your accuracy and be better prepared for the off angle shot.You could be easily around 525 grains with vanes and a 125 grain point(with a 28" arrow).Drop to feathers and 100 grain points,you would be around 472 grains.That would keep your energy high and speed respectable.(not to mention the availability of the bows and resale )


I know most don't actually understand speed but believe when I say it is way overrated.There is a difference when adding 10# as you like to do but it is very minimal,especially for a hunting situation.The big difference you will notice is energy but when you get as high as you are,I don't think the energy is a big help either,you can only penetrate the ground so far before you won't be able to find your arrow.

Unless you are hunting elephant such as Elk's friend,I don't think I would concern myself with it.