I really think you're overthinking your aphid problem MVR. The key to controlling them is diligence.

Here's what i would do---

Take a spray nozzle that has an adjustable spray pattern. Attach to hose. Turn water on low. Spray the undersides of the leaves bottom to top with the nozzle that has the pattern that one would use to rinse their car off with prior to washing it. So, not a jet stream and not a mist. Do this in the morning or evening. 3 days later, do it again. 3 days later, do it again. 3 days later, do it again. Do this for a good couple weeks and then inspect plants.

Still infested? I would move on to something stronger but not any stronger than an insecticidal soap or neem oil. Same thing as the water treatments, but do it in the evening only. And in the morning rinse with water so the plants don't get sun damaged.

With the neem, i would leave it on as long as the daytime temps aren't over 80F, since neem oil has anti-feeding properties.

If you don't fix your problem using this method, purchase some lacewing eggs/larvae and be done with it. Word of caution-- if you have an ant problem, do not release lacewing EGGS until you clear up the ant problem. Ants love to feast on the eggs on the cards that lacewing eggs come on.

Good luck.

Kevin