Why not do more than one thing?
Make sure your radiator is cleaned out and there's good water flow.
Some cars have a larger pulley than others- you can overdrive your water pump with a little smaller pulley for better effect.
The fan clutch should work OK for five or ten years. Take it off, and add a flexalite (or similar) fan.
Change out that stock electric fan with a 2k cfm aftermarket, and get an adjustable external thermostat switch for it.
Add a tranny oil cooler, and an engine oil cooler, and take some of the load off your cooling system.
Make sure you have a air dam separating the front and rear of the radiators- some cars have been known to "loop" the hot air at stop lights and slow traffic.
Then again, I vaguely remember something about a head leak at that location that means that the last guy screwed something up, and you may indeed have a crack.