I'm planning a website that will have a survey of user preferences for various topics. All of the questions are optional although some of them may be more important to users than others. The questions are mostly radio buttons and they can be easily grouped into categories.
I thought about putting each question in a box and then having a grid of questions under each category's header.
The page gets very long on mobile devices however.
I also thought about having a horizontal scroll for each category's questions and maybe having the less important questions off to the side.
I'd prefer that the survey was a single page unless that doesn't make sense for this case.
What's the best way to display this content?
EDIT: I've included examples of the two things I've tried.