The ancients rules that I have been playing and enjoying for the last 15 years or so are Archon 2, the Piquet period supplement that covers up armies up to around 1200 AD. I thoroughly enjoy the games using these rules for many reasons: there is an inbuilt command and control / fog of war mechanism that eliminates a lot of the predictability of igo ugo turn sequence games. There is also a real ebb and flow of battle which mirrors quite well the descriptions of real actions and causes every game to be an enjoyable, edge-of-the-seat affair, with the chance that things will turn your way however bad the situation that you find yourself in.
There is also a lot of scope to give different armies idividual character. The troop types within the force can be described by their training grade, armour, allowed formations and the chance on any given day that they will be battle weary or at a fever pitch of enthusiasm for the current fight. (I do like that there is a small chance that your Praetorian elite guard unit will be having an off day or that levied peasant might be feeling well up for it!) The army as a whole can also have suibtle variation in its character; keener on shooting or getting stuck in, better or worse at formation changes or rallying or superior in close terrain.
There aren’t many rulesets that would allow a game with the smaller army outnumbered almost 2 to 1 to still see off the enemy by having a superior overall plan and seizing the opportunities when they presented themselves.
Hmmm sounding like a bit of a zealot there Ultimately I have found over many years that it is the company not the rules that make for an enjoyable game and I’ll paly whatever is offered if someone has gone to the trouble to organise a game.