I still remember the classic Wappaw composition & strategy for random plains. A handful of infantry and/or crossbowmen, advancing straight towards opposing archers with shields up and friendly cav covering flanks or surrounding the enemy's rangers. They had superb timing, and would bring everything to bear against the enemy rangers all at once. They had enough sense to bring polearms on their infantry, and enough coordination to use them effectively, so you couldn't really straight-up cav rush them. It was quite effective unless you could shoot down their cav before their infantry caught you, and even then you're stuck kiting infantry for the rest of the match.