With most Catholic factions, I like to have lots of polearms and arbalesters in my army, with some cavalry (heavy, medium, and/or light) in support. The arbalesters provide superior ranged fire, and the polearms provide a balanced, capable infantry force that has no serious weaknesses.

The Turkish have my favorite army, and a good Turkish army includes a balance of JHI and hybrid infantry units, as well as a fair number of Turkomen Horse and a few heavy cavalry units for mobility.

The only factions I would go sword-heavy with are the Almohads and the Byzantines (although Byz armies should replace BI with VG wherever possible). BI and AUM need a lot of support from other units to truly be successful.