I have the same impulse to want to virtualise my router. I’ve repeatedly agonised over this but keep coming back to the decision that as cool as it would be, so long as internet uptime matters, the router probably needs to be separate hardware.

You can get good, power efficient pfsense hardware for around $200 USD. A few bonus notes:

—You could spend a little bit more and get hardware that's good enough to add a virtualisation layer to your dedicated router.

—If your uplink is less than 300 megabit, and you have a managed switch with VLANs, your pfsense box doesn't need to be dual NIC. This could open the door for cheaper or re-purposed hardware.