generate the bitcoins based on dwell time
Why not tie is back even closer to the value of the site... have the browser mining for bitcoins (as part of a pool of all Brave users) in the background and depending on how long I spend on a site deposit the appropriate percentage of earnings with the site in question.
the longer I stay engaged with a site, the more it earns. so TheRegister which continues to amuse and inform would get more of the slice of the pie than, say, Wired which daily becomes less relevant...