Hey Jon,
Embeddable forms and responsive design are 100% possible--we have actually had very good success rolling out those things. I think one of the reasons things look a little hacky is that there are several ways to approach all those features that aren't quite "out of the box" yet. Some of them are complex and some of them are a little more accessible.
So far I haven't really found anything design-wise that wasn't possible. You just need to get some really solid templates in place, and make sure your team knows how to use them. You should be able to use a responsive framework, call external CSS compiled from SASS, etc.
Here are some examples of our cooler templates:
http://pages.carefusion.com/ResponsiveTest.html
http://pages.carefusion.com/HIMSS2014.html
Those were both built leveraging tokens--almost all of the elements on the page, including background images and body copy, can be easily swapped in using tokens.