Would creating a niche site related directory be good?

Im thinking about adding a directory to my website.

Would it be usefull content for SE/people?

 

Go for it. I suggest to use a subdomain instead of a folder. Search engines see subdomains as seperate domains so you might dodge a bullet if your directory is banned or hurt from whom you link to and if done right can really help bolster your site.

 

good idea!