For a strategy to keep in mind when your outnumbered, this is what I did with England all the time. This army was generally my raiding army so had no archers, just a couple as spies as well to open gates but that's not important for this.
6 * Heavy Infantry (Armored Swordsmen)
6 * Feudal Knights (English Knights if I had them)
1 General with high morale/command/chivalry
As my army was a smaller stack, I often got attacked by large stacks of enemies so I perfected this strategy. This works best against European armies as Eastern armies generally have to much light cavalry and skirmishers for this to be effective.
NOTE: In several stages things could be very different, for example if you manage you kill the enemy general early, the enemy army will likely rout on the next charge, cutting out easily half of your own losses. Also, I left the final archer unit for last as I needed the additional charges into the enemy line to prevent my own from routing. Play around with this strategy, but it has served me extremely well against large armies of heavily armed and armored foes.
SETUP:
First move:
Second move:
3rd move:
4th Move:
5th Move:
6th move:
7th move:
Hope this helps someone, it was fun to put my strategy into pics and words,