If you're contained to your base in early Castle Age against Malians with their cow economy, there's no hope later on.

You have to put pressure on the Malians and lead the match up through map control with the sacred sites, using Ghazi raiders to exceed the Sofa mass initially. It can get very tricky later on.

When facing Donso, pivot to archers quickly to deal with them.

Against Malians, the play should be Archers and Ghazi Raiders. Javelins counter that, but unless you see a mining camp, they won't have enough gold to scale javelins.

Sofas aren't that tanky in feudal; imported armors is a castle tech. Archers will still be able to do half their damage into those heavy cav.