Personally, I value an email signup easily 5x more than a like.
Due to edgerank, my engagement can sometimes be as low as 5% (in terms of the number of people that see a post out of total likes) for some posts. For my email list, I usually get about 40% of the list that will open the email. Far better quality of results.
I prefer email, twitter, and G+ much more than facebook. That being said, keep in mind most of my marketing activities are informational. For creators, you may expect a higher fb engagement and you might have cool photos of your product and company you can share. If you have time, measure your stats and report back here
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If you have great photos or a product that may resonate with a female audience - Tumblr, Instagram, and Pinterest are also worth looking into.