I found Cry Havoc is a good source for playing unit combat, but sadly is not compatible with B-right because CH units are built from the level of the individual (as per phb), whereas B-right units have been pre-made at the unit level…

The two different economic systems result in serious balance issues when simply trying to convert a B-right unit into a CH unit.

Last year I have begun work on building birthright units from the individual level, as to become compatible with Cry Havoc. As a result the costs of the units have somewhat changed, and some units (notably knights) have become considerably smaller.

The first results are promising but it will still need more play-testing. Consequently I was wondering whether others have experience with Cry Havoc and their solutions. I am also willing to share my findings to those interested, for feedback