What exactly is vague about this?
"No Person shall be a Representative who shall not have attained to the Age of twenty five Years, and been seven Years a Citizen of the United States, and who shall not, when elected, be an Inhabitant of that State in which he shall be chosen."
or this?
"All Bills for raising Revenue shall originate in the House of Representatives; but the Senate may propose or concur with Amendments as on other Bills"
or this?
"Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction."
Now, I agree in portions such as this:
"The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases of Rebellion or Invasion the public Safety may require it."
That what comprises "public safety" is open to some degree of interpretation.
But the document, as a whole is not that opaque.
The intent is to be a transparent set of rules. Ones that you and I, as participants in a democracy can view and insist are followed. We can't just say "oh, judges know better" and leave it at that. That isn't a democracy, isn't representative and leads to a very bad place. We have to demand representation and a rule of law. We can't allow the law to be bent to the point it really isn't law anymore. We, as citizens, must be in control of our government. To do that, we must individually be able to read and judge the rules and ascertain if they are or are not being followed. And elect those who agree to uphold rather than subvert the process.