CPT is absolutely wonderful...but if there was one thing I'd add to it, it would be the ability to export the repertoire in some kind of text format. This would make it very valuable for chess writring. I think simply dumping the candidate move tree would be great, or possibly the entire tree.
This would allow me to take CPT trees and use them in chess writing, pull them into other programs, etc.
Something like:
1. e4
...e5
2. Nf3
...Nf6
...Nc6
2. Nc3
...d5
Etcetera...obviously, the above is simplified.
Keep up the good work!