[tinkthank]

That's good advice so far, here's just a tiny addition:

In general, the answer to almost all of your questions is "it depends", but here goes:

1. Fodder + spells also helps; tie up those enemy cav with some cheap screens of militia or cheap summons (manikin, who also cause nice fatigue, or vine men, or whatever) and hit them with flares, fireballs, or missile fire.

2. Priests help against acute moral drop, but net average morale can be raised by simply having larger squads of troops. Or you can break up your troops into lots of smaller squads, knowing well that a few will route, but others will be there to take their place.