DAZStudio has its own runtime folder within its Library, mostly reserved for textures and other miscellaneous content. A very convenient place for Poser type props and DAZ compatible figures. 3D asset management is a neverending issue in itself. Individuals organize their content by models, others by categories, and still others by vendors and authors. Explore how other users organize their content and why; this will give you some idea on how efficient those runtime setups meet your criteria. I set up my folders according to models, scenes, props, and hair. I have a couple of runtimes with clothing but I'm not too keen with those setups so I might split those up into their associated models. Again, there are pros and cons, find something that works for you, modify it and stick with it. The last thing you want to do is start a project and wind up completely moving content around because it just didn't work.