I don't like the idea that some courses would become second-class. I agree with Jim that the information is already in place to determine which courses are record-quality and which are not. I don't see why most events would care whether their course is record-quality or not. It's generally handier to have start and finish close together, but records don't loom very big in the thinking of most race directors.
The record-keepers are smart enough to figure out whether a course is record-quality or not, and those who are likely to set records are so few that it seems overkill to complicate our numbering system.
Certification deals with course length. We do record extra data (drop and separation) but it has always been up to the record-keepers to sort things out regarding "record quality."
USA record quality is less than 1 m/km drop. 30 percent separation. IAAF record quality is less than 1 m/km drop, 50 percent separation. Would this require yet another number adjustment on the part of certifiers?
Let's not make a mountain out of a molehill. Leave the numbering system alone.