Gamification is not a new concept. Many companies have been using it to keep their audience more engaged. You could always use this concept to make your community a more attractive place for your readers and new visitors. WP User Achievements is a handy plugin that could help with that. It is an interesting script that brings user badges to your website without you having to do major changes on your site.
The WP User Achievements plugin comes with 11 achievements automatically assigned. Your visitors will be able to earn points by participating in your community. They will get gold, silver, or bronze medals for their performance in each category. You could also create custom badges and assign them to certain users for things they have done to enhance your community.
The WP User Achievements plugin is fairly easy to implement and will most likely not mess you theme. It is worth testing if you would love to increase user engagement on your website.