If you're interesting in extending DBA into the Renaissance period, here is a helpful reference from Allan Redmond:
In response to Myrmydon's inquiry over renaissance DBA I suggest he find someone with back issues of Wargames Illustrated. Issue no. 71 from Aug. 1993 has a very good article which extends DBA to cover the period 1450 - 1700. It introduces several new troop types such as reiters, arquebusiers, musketeers, bayonet musketeers, pike and shot, and dragoons. Appropriate combat factors and outcomes are provided. The simplicity and ease of learning of original DBA is maintained. And, joy of joys, it adds a list of 90 new armies to add to your collection of lead. Check it out. I highly recommend it.