Many years ago, I owned the first edition of De Bellis Antiquitatis, a set of fast-play ancient rules. [I just discovered that the original DBA rules can be found here]. I played a number of battles with my 6mm Romans, Gauls, and Carthaginians, but eventually I soured on the game. The rules worked great for Roman vs. Gaul battles but when you pitted similar troops types together (e.g. a Roman Civil War battle), the fights seemed to turn into indecisive shoving matches. When Battle Cry came out, I turned to the Command & Colors system (which has inspired my horse and musket Francesian rules).
When I began my medieval Francesian projects, I ultimately turned to the C&C system, The system just seemed to play too fast in my raid scenarios so I began pondering a new approach. I thought back to Song of Blades and Heroes, a system I considered last year. At the time, I decided against it primarily because it was designed for individual figures where I wanted stands representing warbands. Recently, I read where someone used a set of skirmish rules for larger battles by treating a stand/unit as a single figure. I realized I could do the same with SBH. Reading the rules again, I realized that they essentially used a DBA-like opposed die roll system but somewhat solved the shoving match issue by having figures "fall down" when beaten but not doubled. Figures that "fall down" suffer penalties to later die rolls. I decided to experiment with SBH.
After some thought, I decided to keep 2 stands to a unit, with each stand able to suffer 2 hits before being removed. A unit takes 1 hit if beaten in a combat and 2 hits if doubled. Once a unit lost a stand, it suffered a penalty to its combat roll. I also wanted to include mandatory retreats so I decided to use an extra roll against unit Quality (SBH uses 2 stats per figure - Quality and Combat).. Failure forced a retreat. Alas, I kept forgetting to roll for retreats during my test battle. Nevertheless, I felt that the combat system worked well. Fights went on longer than with my C&C inspired rules, but did not drag interminably like DBA.
I also used the SBH activation system (which I describe here). Infantry move 1 space on the battle grid per activation (heavies are restricted to 1 movement activation per turn while lights can use 2). Attacking with 2 activations provides a bonus to the combat roll. This activation system provided more tactical thought than simply rolling pips like DBA.
Overall I enjoyed the game and will continue to experiment with a SBH-inspired system.