From an SE standpoint, any resource that provides human reviewed data or citation data is of value. Typically human reviewed content is unique in nature and offers a depth of quality that cannot be achieved through normal algos.
Personally, the global directory concept is flawed for a startup directory. There is no way that you are going to compete in that space at this moment unless you have an army of paid editors.
I see niche directories being King of the Hill now and in the future. The only way you can really start something in this space is to do it differently than everyone else. And, you better have the time and patience it takes to get your directory seated for future growth. If you've got the finances, you can speed the process but not by much. ;)
If you have a passion for something, whether it be a particular region in the world or a certain industry etc., developing a directory around that passion is a great start.