Stephen, so many problems with your thesis ... and so little space to reply.
1. Your definition of death is weird.  Death of the body is the cessation of bodily functions which support consciousness. Turnover of atoms/cells is irrelevant.
2. Your definition of 'soul' assumes the correctness of SDA/OT materialist view of human nature.  SDA reliance on Eccles 9.5 ignores its context.  Eccles 9.5,6 supports a Sadducean view that our limited material existence in this life only is all that is open to us.  9.6 '... neither have they anymore a portion FOREVER in anything done under the sun...'
3. The NT describes 'death' as the state of existence in separation from God, the Source of Life.  eg, Eph 2.1  '... dead in trespasses and sins...'
4. Life is the state of renewal / new creation by the Holy Spirit.  'That which is born of the flesh is flesh, that which is born of the Spirit is Spirit,'  '... passes from death unto life.'
5. Our future state is spiritual/immaterial  Matt 22.29-32