How is it that when I compare an equal dose of ibuprofen to acetaminophen that the former has a much more beneficial effect? Many feel this way too?

Different molecules, thus different responses: Look each up using Google images. Add the word "molecule" after each generic name respectively. Comparing mg is only useful if the exact same molecule. All bets off when molecules are different. Essentially all prescription meds are a single molecule, tested at specific amounts per unit time, called dosages. Why? Study: https://en.wikipedia.org/wiki/Therapeutic_effect.