After doing more in depth analysis I think the battery drain has to do with the reactivation of iTunes sync. You have do enable it in iTunes then disable it immediately.
I don't know why but it seems to fix the drain and heating issue
But you only use your phone about 4 hours out of the day. Most people here use theirs more per day. Still good usage though.
When I got my iPhone 6, I was getting 19hrs standby, 9+hrs usage.
Since updating to the new iOS' since coming out, it's dipped to about 15hrs standby and 7hrs.
Anyone have any idea why? My top 5 usages are Home and Lock Screen, Facebook, Messages, Twitter, Safari.