Hello Fellow Moz'ers:
I own a small digital shop in a major US city. We had a marketing idea which I'd like some input on the soundness of. We are creating a professional services directory of 'digital professional services providers' in our hometown. The directory's membership will only be open to firms located within our city limits. The directory will be curated and maintained, ongoing, by us.
Our motivation is 75% selfish and 25% benevolent. The idea is that, by building the directory on our subdomain, we hopefully will collect links, which ultimately will enhance search visibility. But I'm concerned about the devaluation directories have incurred in recent years and I've even seen advice given to the effect that listings in some directories might be harmful to a site's link profile. It is not our intention to harm those who might list in our directory.
Any thoughts on this matter would be greatly appreciated!