I like HubPages so I write for it. The backlinks to my sites are good and the AdSense income is a bonus. So far I have about 30 hubs (under 2 author names) and I make about $5 a month. That said I do almost nothing to get them noticed.
I think that HubPages is a lot like any other site. Pick a topic with a lot of natural traffic. What does Michael Jackson's death mean? How do I make money online with ...? I think you get the point.
Once written you need traffic. Getting Google organic search results for your hubs is easier than for a brand new domain but not as easy as Ezine. However, Ezine doesn't share revenue. So some people write a partner article on Ezine pointing to their Hub where they get AdSense revenue and more often than not they are promoting an affiliate product.
Past that I'd say consider your hubs like you would any other website you own. Consider the SEO of the article your write. Consider creating backlinks to individual articles and, more importantly, to your Author profile which will act like a home page for your hubs.
I just write for the fun and the backlinks. I haven't really attempted to do much SEO for my hubs. So all my advice is just conjecture.