Replacing the cables can make the lever FEEL better but it won't make the lever effort needed to stop at a given rate any lighter. For that you will want to exchange your single pivot calipers for dual pivot calipers. Tektro makes dual pivot calipers in a wide variety of reach ranges. If you need something more than the modern road racer short reach caliper they have a 556 and 538 long reach in two ranges to choose.

Going with a dual pivot caliper and combined with the salmon color pads will give you the best brakes you can get. Top it off with a switch to a good housing with smooth shape cables and it'll feel as good as it stops.