I wouldn't suggest an alternative funding model as much as guess what will it be maybe a year or two from now. Key quote from the article:

> Mozilla has launched Monitor, a data-breach reporting service; Lockwise, a password manager; and Send, a privacy-focused alternative to services such as WeSendit. It’s also beta-testing a VPN (virtual private network) service, which it hopes to market to privacy-conscious users.

Once these web apps mature a bit, I expect to see them in a free tier + a premium behind the subscription (with the core browser of course remaining free). My hunch tells me that's why you'll see this front-and-centered if you open mozilla.org:

> Firefox is more than a browser. Meet our family of privacy-first products