Hello!
Thank you for your article.
Just a correction on the quoted part. That's not possible because the Tor exit-node does not know your "real" and/or your "VPN" IP address. In general the exit-node receives all the traffic from middle-relays, which in turn receive the traffic from Tor guards (the entry-nodes).
As far as it pertains to your purposes, consider the following setup, especially when high throughput is not a priority:
connect the host over "OpenVPN over Tor"
run a Virtual Machine attached to the host via NAT
Tor-ify everything in the VM
use end-to-end encryption, exclusively
use only VM traffic for any sensitive task
The above setup, we think, should meet all of your requirements. Furthermore, the main fault of "OpenVPN over Tor" (fixed circuit) is completely resolved by Tor in the VM.
Kind regards