If you have a copy of the original 3.0 discs (or the digital downloads from back then), you were sitting on a goldmine of over 1,500 emitters. However, the specific builds up to July 2007 contained some gems you can’t easily find in modern packs:
: Capability to render up to 8K resolution for use in other compositing software.
You might ask: Why bother with 2D sprites from nearly 15 years ago?
Before After Effects had its built-in particle playground (and long before Trapcode Particular became the king), there was Illusion . It was a standalone application famous for being incredibly fast and using a library-based system of pre-made "emitters."