is there a DLC system like in video games for adobe that allows you to add on extras and what not
Some Adobe products make use of an extensions system that allows them to load in extra features. Others use presets or libraries that can be shared between programs or users. Many Adobe products also accept third party developed plugins like Photoshop.
There are a few internal referencing services like Kuler but it depends on the program you are using as to what is or isn’t available.