Looks like an awfully nice bike to me. Although the mechanical advantage means that you'll never have as light a pull as dual pivot calipers, it is quite common for older brakesets to require high effort due to high drag in the cables (due to lack of lubrication or wearing through of cable housing liners), hardened brake shoes, and corrosion/lack of lubrication of the caliper springs and pivots. That bent over at the lever front brake cable is probably a major contributing factor to bad braking all by itself. Do a brake overhaul including cable, housing, pad replacement and your braking will likely improve dramatically.