I'm a big fan of the software lists because they're too convenient to simply pass up. When a site like PD can offer complete software lists for ROMs and CHDs for [FREE] it's simply too much value to pass up.
Once you insert the root paths of the software list ROMs and CHDs into your mame.ini you'll automatically gain access to an enormous amount of content. You pair that up with a proper frontend like QMC2 and you've quickly gained access to thousands of different machines with a support system that's relativity simple to use and execute.
Although this blog post is over 8 years old, a lot of the information still holds true today. Perhaps it can answer some further questions.