The most important factor to bowhunting is KE. KE is king. That being said, you must have some speed to get the KE. Three things you must have and the trick is to balance them to your liking.

1 - KE
2- speed, to some degree
3- silence

You will get enough KE shooting most of the setups offered today. To me the most important factor is silence. How quite is your bow? I don't care how fast your bow is if it is loud the deer will jump the string. Sound is much faster than any bow made. IF you are shooting 350fps and your bow twangs real loud, no deer. If you shoot say 250fps and your bow is whisper quite, venison in the freezer and your kids don't have to eat ketchup soup all winter.