Adding some output options for the custom fields would be a big improvement. For example if there were some predefined elements with corresponding tags as you see in a lot of different Joomla extensions representing certain elements then you could expand the functionality and usefulness of the custom fields exponentially. So let's say there were a tag representing what a user input into a text field. If say this user was one of the moderators assigned to a question category, they could have some expanded functionality to include in their responses. The output options for that field might be something like:

• a predefined path to images:
  
<img src="/images/qa/TAG" />

• a predefined video provider:
  
<source src="//youtu.be/...etc/TAG" />

• an obfuscated /key linked document not available anywhere outside of the particular Answer:
  
<home/site/notpublic/qa/TAG" />

that is just one possibility. You could also matchup values and categories with the corresponding element tags or custom urls with a url type tag. "TAG" as in the above example would pull from the input data in practice "TAG" would be like:

{TEXTFIELD}, {URL}, {OPTIONVALUE},{TITLE} etc/