Since you are already getting pass throughs, the only thing a heavier arrow would really do for you is quiet the bow down a little. It only takes 55-65 ft.#s of KE to take on animals as big as moose, elk, etc. Deer are more in the 40-55 ft. # range. Heavier arrows will also make you increase the distance between your sight pins, as it slows down the arrow. Personally, I think you are in the right zone with the setup you currently have.
2006 Rytera Bullet X 60#---2008 Moab 70#
2008/12 Firecat 60#--- 2010 Warthog 70#
2010/2012 Alien X 65# 2011 Onzas 60 & 70#
2009 Warthog 70#---2009 Firehawk 70#
2010 Strother SR-71 65# & 2012 Strother Rush 65#
I hunt, therefore I eat. lol