I could see one that focused on CDC / nih data and communications. I use clinicaltrials.gov all the time for work to look at study designs for big clinical trials, could be cool to have an instance that covered info from there. I could see another one maybe for weather and traffic related data from NOAA, state highway authorities, etc. maybe another space related one for NASA and space force (lol). Others for the military branches, it goes on and on. The government has social media accounts for most of these services already, could give the fediverse a big boost if their content is directly hosted on government servers