Jan van Leyden
Adventurer
Wizards did something similar to this during third edition. It was called e-tools. You paid a certain amount for the base character builder program and then a smaller amount for the data files for each book. The management of the program changed companies and was eventually dropped before all the books were completed. It was less than ideal. The good thing is was that it did work offline but I paid a good amount for e-tools data files and I suspect I would have a heck of a time getting them to install now.
I'm probably not the only one who doesn't want to witness a repetition of the Mastertools/E-tool debacle. When this piece of sotware came finally out it was several years late and completely unusable.
Only when a group of PCGen developers formed Codemonkey Publishing, took over the project, and struck a license deal to develop the data sets for E-Tools and PCGen did something useful appear ob the scene. Even then, data sets for new books took a very long time to come out.
So, no, please don't take this as a model!