One idea is to modify an off the shelf WP theme to produce a workable product. My goal would be to get an off the shelf theme like this:

https://www.appthemes.com/themes/clipper/

In the ball park of:

https://www.hotukdeals.com/

In terms of UI/UX; the needed features would be ability for a user to upload content, upvotes, plus some basic forum functionality, comments profiles etc.

How viable is this approach?