The bigger thing for the converter is making sure all the conversion rules remain accurate through changes to either game. Right around the time the CK2 team was busy with a major release. Broke the map, broke several culture conversions, broke some religion conversions.
Case in point, the EU4 patch alongside AoW. The big problem with the converter is it seems to be under the CK2 team's responsibility, yet the things that break it most are changes to EU4. I do think it will have only mild to moderate usefulness as far as the converter.
