What Congress might do with Biden’s support is to statutorily reduce the excessive number of positions in departments and agencies that are political appointments. The person at the top and their chief deputies in the next layer should be the only appointees, and even then for many agencies they should be required to have expertise in the subject they are administering. Lower down should be all professional civil servants.
The US has an incredible number of political appointees in every aspect of government administration compared to other First World countries.