I wouldn't worry about the traffic. RSS feed directories can be ok as a small part of your SEO strategy to get additional backlinks to your hub / articles, but they're rarely ever going to drive significant traffic to your website.
One thing you can do is create a microblog (i.e. Tumblr) for the specific purpose of syndicating your hubs. Every time you publish a hub, create a link post on your Tumblr blog with a quick description of your hub. Not only will this raise visibility of your hub and potentially draw some visits from Tumblr, but Tumblr will then create an RSS feed for your Tumblog which you can submit to directories or aggregators.
It's kind of a round-about way of doing things and requires a little manual work on your part, but it should work. It also lets you split up your topics into multiple feeds or Tumblogs neatly. Say, for example, you write about photography and education (like I do). Create two Tumblogs, one for each topic, and post the link to the hub on the most relevant Tumblog.