Lots of good stuff and hard to explain. Everything before the power zone should be building leverage/coiling and momentum, then it's an unleashing/whipping of the levers/coil and massive heavy momentum of the disc toward your target. You are foggy because you don't know your hit point/destination. If you are stuck on the right pec drill, you should go the closed shoulder drill and or check out the hammer pound drills/secret technique. In your original question, you state you think you understand how reachback and inward pull work but not the outward throwing motion. If you understand that the backswing/reachback is the takeaway from the address or hit point then you should not have a problem.
This is part of why I advocate using a pre-swing/forward press like Feldy or Shultz and working your body around the disc instead of moving the disc around your body in the x-step. It's much easier to load your body to a stationary object and get leverage on it, than it is to heave an object back and try to maximize your body leverage to bring it back to the hit point. It makes your body move in one fluid motion rather than a multi-piece throw. When doing a standstill you will have to move the disc back and forth but it should be effortless from the arm, your hips should bring the arm/disc unit into the backswing from the hit point/address as if the disc were a sledgehammer.
As far as elbow bend, the important thing is to lead the thumb with the elbow as far forward toward the target as possible before whipping the lower arm. Closer to the chest typically helps accuracy and increasing lower arm acceleration. Getting further from the chest typically reduces accuracy and slows lower arm acceleration but creates more leverage.