2. the price will likely go down and down and down,
Not necessarily. Once the 8MB version gets 75% miner approval, the other 25% must promptly switch to it, from self-interest. Then hopefully no one will pay attention to the Blockstream FUD anymore.
3. After the fork find someone who owns coins not existing on the both blockchains and ask them to send few satoshis to your account, do it for the both blockchains. Those lucky owners of coins that don't exist on the other blockchain will likely be miners or guys who managed to get their transaction not included into the other chain.
As per above, it will be very difficult to find such miners. If and when the chain actually splits, every miner who cares about his money will be on the 8MB branch.
I expect that the market will react to the fork by selling such special coins slightly more expensive than their face value.
Since those coins will exist on a chain that will be issuing only 1 block every 2 days, "slightly more than its market value" may be zero plus 10%.
Not worth pointing out the problems with the other steps...