Featured Hubs are the Hubs which pass all the quality guidelines of Hubpages. They use multi capsules and possess quality, useful content supported by good images and other engaging capsules such as poll and quizs to make it more interactive.
The trick is to choose the most appropriate category for your Hub instead of going for popular categories. Remember lesser the featured Hubs in a topic, greater the chances of your Hub featuring in the top thus gaining more exposure and readers.
Position of your feature Hub changes as per it's popularity i.e. number of comments (engagement) and shares on social media networks. Also you may notice that when you publish your Hub and it is approved and featured on the Hubpages, it may not appear in Topic section. The reason for the same is exposure and popularity of your Hub vis a vis other published and featured Hubs in the same category/topic.
I hope it helps :-)