DCC is an old standard, when memory was expensive, so things are in binary instead of ASCII characters.
The indexing system to get more "variables" is again an old limitation.
Nowadays this could all be done in normal characters.
Of course the solution is to use a high level graphic interface program like CVManager. Many of the decoder manufacturers who have complex functions have a nice computer program to set things for the non computer science people.
I'm surprised no one suggested CVManager here.