The idea was that the Repertory contained wisely selected information and that additions could only increase the bias of too much information. The book is complete. But a conversation has been reported, shortly before his death, where he contradicted his wife who was making the same statement. If it had to continue, his students had to take care of it.
Today there seems to be little doubt as to the necessity of additions.
Although some consider it as a Repertory, it is a full text structured line by line. It takes much time to transcribe it to a correct repertory structure, but the book is being integrated into Kent's Repertory. Other Materia Medicas have been integrated, although most of them partially, due to the amount of work involved. Clarke's Dictionary, William Boericke's Materia Medica, Phatak's Materia Medica, Borland's books, Tyler's Drug Pictures, etc. Many other homeopaths have done great jobs on particular remedies taken from different sources, or from research according to their interest.