Hello,
I don’t think it is an understatement to say that at least a hundred people have used the API to create apps already. We are happy to provide support for API related questions, should you have any, and will be focusing on more API (and app related) development with GD V2. With the API you get more control over creating listings and wouldn’t be subject to the core import logic, which, btw, will be improved in V2.
During an import CSV can be great, don’t get me wrong, I just wondered if you were planning on syyncing incremental changes as you build up the directory, or if you were looking to maintain a secondary (or primary, other) DB for point data, specifically, and if CSV was part of your long term workflow solution. Might install the API on a dev site and try it out with something like this: https://insomnia.rest/