I've been helping others solve their cooling problems for decades, and 99% of the time it's basics - either the radiator or airflow. Cooling systems are very simple - assuming the thermostat and hoses are OK, there's not much left (have NEVER seen a water pump responsible for a cooling problem). Only two things matter - the efficiency/abillity of the heat transfer device (the radiator) to transfer heat from the coolant to the outer surface so air can carry it away, and the adequacy of the airflow through it to carry off the rejected heat. The former is affected by age/internal scale and corrosion (nobody ever expected Corvette radiators to last for 20+ years when they designed them), and the latter is a function of sealing the radiator to the support, correct shroud, fan, and clutch. The stock system ALWAYS works best if it's maintained properly - it was designed to do the job. Electric fans, "water-wetter", etc. are "band-aids", usually found on butchered aftermarket cooling systems that "look cool" (but don't really cool) like a "race car". If you add more motor (that rejects more heat), just add more radiator, but leave the rest of the system in place - never had it fail me.