Hypothetical: As a company if I did not want to switch to https from http due to the SEO value (knowing this could potentially be small, but would have a huge impact on next year's financial forecasting) is it possible to build responsive iframes around forms? If yes (I'm hoping this is the case), is there documentation that could help steer a person in the right direction as far as executing this?
Adaptive forms itself are responsive, what you can do is create a custom adaptive themes using responsive iframes. Since AEM forms itself is a web application you can use any html/css/js based framework. One such example for creating custom theme is referred in the following link
You can use similar approach to achieve your goal.