While it may be satisfying for the OCD within you to manually organize your digital mementos into albums in Photos, you can automate the process using smart albums. These albums self-populate based on criteria you set, so when Photos detects an image that matches your criteria, it's automatically added to the smart album (just like iTunes' smart playlists).
These ideas barely scrape the tip off the smart album iceberg. The more you use them — and the more you employ Photos' favorites, keywords, and faces tags — the smarter your Photos experience becomes. Until the next time, may the creative force be with you all!