The free basic version of Impetus Fantasy is still around and the commercial release version is being written and tested currently.
Uses the mechanics of Impetus/Basic Impetus so is a great mass battle game. The magic in the basic version is a bit weak (but more extensive variants have been done).
Works by allocating unit stats from historical archetypes; so you can decide if your Fantasy "Knights" are like Sarmatian Cataphracts, Crusader Holy Orders, Renaissance Gendarmes or something else.
Units are single bases so reward diorama style basing.