Amendments 5 and 6 are often credited to the writings of Brutus, the Anti-Federalist, maybe the most cogent of the Anti-Federalist writers.
The Bill of Rights was not as much a matter of dispute as to how it would appear to the public if rights were made explicitly. Some feared (and rightly it turns out) that if you appended a Bill of Rights you would be saying that the government is thereby conferring those rights whereas it was well nigh universally agreed among the arguing parties that those are God-given rights.