The advice has always been several external runtimes categorized and organized in a logical method.  Most content files should be kept together so that internal actual/relative path references be established without searching the entire folder.  The latest generation 4 DAZ models require installation into the actual Poser runtime, although many users have successfully managed to install and maintain these files in separate externals.  It is adviceable not to separate content from within their own established category folders, eg removing texture files from the Textures folder into a differently named folder.  That will break the internal pathway convention, which will force you to search for content when loading a model.