The NFL should have split the season into segments. 1st segment lasts 8 weeks and all teams play all 6 of their divisional games. So basically there are 8 little bubbles of 4 teams each. These are the most important games so get them out of the way first.
Next segment teams play their 6 conference games, last segment they play their 4 non-conference games. So everything is nicely compartmentalized with extra bye weeks between each segment.
And because of the symmetrical way the Divisions play each other - for instance the AFC East plays the NFC West this year - It is a lot easier to keep the teams who are playing one another on the same page in case of an infection.
So they could have effectively played the entire season with a series of mini bubbles.
They could have also used the strategy to basically lengthen the season and Put more games on national television, raising revenue.