Here's one thing that would be minor for you, but major for people with low vision or near blindness. I administer a Pagelines DMS site that is nationally read, and the author is a well known disability rights activist. He is also blind, in the sense that if he puts his iPad up really close to his face with pinch-zoom, he can use the web (and does). However, he and many of his users are unhappy with the trend in responsive design that disables user-scalability on devices because of the erroneous assumption that if a site is well-designed, it shouldn't need to be zoomed. That assumption is only correct if you are assuming your users aren't almost blind, or low vision.
I really wish you'd just put a check box somewhere that would allow the responsive theme to enable user-scalable=YES ! It would really help a whole community of forgotten and overlooked web users, and it wouldn't take your developers a ton of time at all.