What are the benefits and drawbacks of having a health program that varies by state versus having one that is uniform across the country?

What are the benefits and drawbacks of having a health program that varies by state versus having one that is uniform across the country? Do you find the positives of state flexibility outweigh the negatives or vice versa? Does your analysis change depending on what populations are served? Does your analysis change depending on whose point of view you consider? Is it fair that similarly situated individuals may be treated differently in different states?