Even the enumerated powers themselves weren't specific enough.
"To regulate commerce among foreign nations, among the several states, among the indian tribes, ... "
That certainly doesn't point out what bureaucracies may or may not apply. I'm not sure how one just assumes that any regulatory legislation is authorized via this clause, but it certainly seems as though it is based on how congress seems to look at it.
The constitution is vague as hell, and we need to amend it to clarify just what would be considered "necessary and proper" to carry out those powers in today's world.
One must ask why the framers saw fit to specify certain things and to be vague with others. This can be done with a very simple set of questions with some very simple conclusions.
Necessary and proper is a phrase that is purposefully left open to debate and interpretation, so that it can be used 'in today's world' or in the world of any other time.
Clarifying it in an amendment, for the particular circumstances of today would be tantamount to throwing out the baby with the bathwater.
We have a representative republic with three branches of government along with certain checks and balances. This and our type of democratic politics is the framework we've always used to
consider/interpret how to carry out powers granted.
It works. It is a slow and deliberative process, but it works. As tie passes what seems of grave and immediate concern usually ends up just being populist or progressive bullshit.