When discussing re-opening/closing down/staying closed, we should pay close attention to hospital and ICU availability. States across the US didn't order shelter-in-place recommendations in order to prevent infections or necessarily save lives - it was really about flattening the curve to allow for medical capacity.
Thus, it should be a highly localized approach. It's a fine line between being reactionary and precautionary, and I don't envy decision makers at this time. However, some smart motherfuckers have already done some of the math for us:
https://www.frontiersin.org/articles/10.3389/fpubh.2020.00262/fullThese authors propose a gradual release strategy, wherein a large portion of the population is released initially, followed by a period of 1-2 weeks after after the end of an infection peak in community spread before a smaller potion is released back to work, followed by 'second peak' 1-2 months after the initial release (where we could be heading in 1 month), with the remaining population remaining population in quarantine for another 1-2 weeks.
This is essentially what some states have already been doing. Unfortuantely, other states (many of the red states in the top figure), employed an on-off release strategy, which will likely overwhelm their healthcare capacities.
tl;dr: States should pay close attention to the ICU occupancy and employ 1-2 week waiting periods of a gradual release strategy of their populations to make more informed decisions.