It depends on the area the battle takes place. An open battlefield where a horse can maneuver and you can see your enemies from a distance is very different from a dungeon or a dense forest.
Mounted archers will dominate in an open plain where they can full attack as they move away but are tactics like this are useless inside a building.
A mounted character using a lance is devastating when they can charge but are limited when fighting in a forest full of tree's and difficult terrain.
I accidentally almost TPK'd my party with 2 Mounted Rangers and 2 Scout that were guarding a convoy the players tried to ambush. I had to cut the players a little slack and allow the scouts and rangers to make some major tactical errors for the players to even survive, and even then the players only escaped, they didn't win. When considering mounted combat terrain is even more of a factor than normal.
Mounted archers will dominate in an open plain where they can full attack as they move away but are tactics like this are useless inside a building.
A mounted character using a lance is devastating when they can charge but are limited when fighting in a forest full of tree's and difficult terrain.
I accidentally almost TPK'd my party with 2 Mounted Rangers and 2 Scout that were guarding a convoy the players tried to ambush. I had to cut the players a little slack and allow the scouts and rangers to make some major tactical errors for the players to even survive, and even then the players only escaped, they didn't win. When considering mounted combat terrain is even more of a factor than normal.