I think 300 dmg x1.5 vs infantry and buildings would be sufficient. Maybe x0.5 vs artillery instead of x0.33. What the SM most needs a big buff to its range. Raising its range from 28 → 32 and LoS from 30 → 36 would be a good start. Usually when I lose a SM it is because it targeted a unit at the edge of its range and ran to the front lines to get in range.
I suggested a few buffs to Ethiopia to get them in better shape, but not too focused on the influence generation rate. Moving Jesuit influence back to age 1 and making cannons more accessible were my main points for that.