Finch:
First, Kinetic Energy is as important for traditional bowhunters as it has been in Army Ballistics and rifle hunters for well over a century. Remember, the laws of physics apply to rifle shooters, compound bow shooters, as well as traditional bowhunters.
Just keep in perspective what it is you want to accomplish and how much Kinetic Energy you need to hunt with. You won't need as much as some would have you believe.
Second, in my opinion, I would be very careful with the concept of very heavy weight arrows being more effective than lighter arrows. Many traditional archers think you need 650 grains to hunt with. If so, how is it that many compound shooters are getting away with about half that?
Again, you should have some perspective on the issue.
If your arrows are well tuned to your bow, and your arrows aren't noisy, then you can kill any North American game animal with 55# because it will provide sufficient Kinetic Energy to provide pass throughs on a regular basis. In fact, a 40# bow with arrows well tuned to it will have enough Kinetic Energy to kill any North American game animal. Heck, Ted Nugent's wife is shooting Zebras in Africa with 38#.
So, your 500 grain arrow is fine if it flies well.