On first impression, one would think that this is already what steem does... but posts fly off the front page in seconds unless they're interacted with, so I'm sure an algorithm could be come up with to estimate the value of the time that a post spends on the front page. It would be even cooler if you could target your audience, or if you could see stats about time of day and viewership, even cooler if you could see that based on audience interest... lol!