Just a couple of remarks about this; obviously this is a whole field of study.
If you test folks without symptoms highly suggestive of infection, most positives will be false positives, leading to unneeded therapy and quarantine. That's just the nature of the test, as no test is perfect. That's why the proposed drive-through testing centers where everybody and their dog gets tested may be counter productive. Doctors will find it VERY difficult to deny tests if a patient wants one even though not indicated.
Testing everyone in a certain group where the infection is known to exist is valuable so that researchers know the penetrance of the virus, i.e., what % exposed will be infected, what % will develop serious disease, etc.
Since the symptoms in healthy folks are so similar to the common cold, the true number of folks infected may be much higher, which means the mortality rate may be much lower than it appears, e.g., 1000 are infected but only 100 get really sick and get tested and 1 dies, so death rate looks like 1% but in reality is 0.1%.
Meant this to be helpful not pedagogical, so forgive me if it comes across as such.