Was it necessary for congress to step in and further regulate independent agencies

There are some many factors that may be consider every time that Congress steps in and further regulate independet agencies. For example, new technologies or new data on existing issues and process. When some petitions iniciate in social groups of interests, corporations or members of the public, the Congress has the responsability to raise their demands to the level of new regulations. Some Presidential directives can also become a trigger for new regulations and it’s recommended that the Congress collect this responsability and study it well. Other agencies can request to the Congress new studies or recommendations for another agencies, too.

The correct answer is: Congress does not regulate an independent agency, the idea of independence itself explains it. It's not necessary. Thoses agencies are created by the congress to work autonomously.

Independent agencies operate outside federal executive departments. Those agencies are constitutionally part of the executive branch and they are free of presidential control. Congress has created a number of independent agencies to help administer several issues of federal government's power and authority. To create an independent agency, it all starts from the Congress, passing a statute granting an agency the authority and autonomy to regulate and control a specific area or industry.  

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