You'd already won this one before it even started, given how out-classed your enemy was. They'd have been beaten so quick no matter how you did it, that you never really had an opportunity to express tactics here.

That said for the hammer-and-anvil it's typically better to keep your main line in a static shield wall formation. They're not meant to be doing damage, just buying time while your other forces position.

Cavalry can easily mop up the archers. It's better with a move command onto the unit and then a charge. The charge command sends them all over the map.

And when you're flanking the main enemy line you should either a) do it with ranged units so they can all engage without crowding each other like we saw here or b) drag them into a longer shape behind the enemy, going wider, before you actually finally send them in.

Wouldn't really matter here, but for other fights against a more developed enemy, it will really shine.