Does it make sense to use Darrel's DT_INTS-14.bas & IOC_INT with ADC or would it just be firing way too often?
no IOC is change of logic level ie 0 to 1 or 1 to 0 not change in adc value

if your adc readings fluctuate that much are your adc settings appropriate ?

why not quantise your adc readings to a finite range of pwm values

see these examples about int driven adc measurements
http://www.picbasic.co.uk/forum/showthread.php?t=21072