I was thinking the same thing as Tree man. 600-650gr arrow is my preference. You usually have to luck into POC that will end up that heavy. One thing to do is to go up a spine class or two, and then switch to 160 or 190gr heads. Also, if you use gasket laquer, you can dip the shafts more than you would normally to bump up the weight. With 160gr heads, I can usually find POC that will yield at or near 600gr.arrows. You may also want to consider the switch to a heavier wood.
Just my opinion,
Titan_Bow