Pulleys, CAI, and exhaust is like the 1st mod you do. That's 'pushrod 101'. Yes, if you have 8 thousand pounds of stereo equipment, probably not good. They do not make your car overheat but if you put a big load on your charging system at idle, voltage goes down, current goes up, and you start putting a strain on stuff. But as soon as you rev above 1500 all is back to normal. Your thermostat is a huge restriction for flow, ever look at one when open? The have a 2" diameter, and the water gets passed through a 1/4" orifice.
The Fox guys run pulleys with their shitty 75-85 amp alternators, you can do it with the 130s. Just sayin'. I kept my stockers just in case, maybe I should sell them. I think you guys that are against them have to have been having other issues. Lights dimming at idle is the only thing I've seen, but how long are you in idle?