Flickr launched in February, 2004. I created an account and started uploading photos in March, 2005. So I guess I’m a long-time user. My primary photo repository is the Photos app on my MacBook (mirrored in my iCloud account): 2,449 photos. I make some effort to only save “keepers.” Flickr is where I post photos I’d like to share with the world. All under Creative Commons license for unrestricted use. I have about 2,500 photos in my photostream organized into albums and collections.
This 12 minute video (I know, too long) is a very cursory explanation of how I use Flickr’s Batch Organizer to manage photos.