Everything seems OK until the last part. The wire CANNOT simply hang from the above framing. NEC code states that the wire must be secured with a Romex staple a minimum of 12" (unless not possible due to water heater location) from connection point at the water heater, and then secured every 18" along the length of the wire back to the panel as necessary. Usually a 2 x 4 is attached to the concrete block wall from the ceiling (vertically downward), and the wire dropped from the floor joists above is attached to the 2 x 4. Also, since it is a residence, MC (metal clad) cable is not required, but is optional.