Any arguments against eliminating all (non-blog) subfolders?

[NueMD]

Short URLs seem to do the trick from a UX perspective. For example: /primary-care vs. /why/specialties/primary-care . This convention will be applied over 30-40 pages. Note that while "/why/specialties/primary-care" isn't terribly ugly, some of our pages would look a little overly-keywordy if we go with the subfolder approach.

[KeriMorgret]

Having some level of structure in you site can be helpful for analytics, too. For Moz for example, we can look at everything happening on the blog by looking at /blog, everything on Q&A by looking at /community/q/, etc.

[TakeshiYoung]

I prefer shorter URLs, but it depends on the size and structure of your site. If you have tens of thousands of pages, then using subfolders to organize things probably makes sense. Likewise, if your site has 5 main categories, it may make sense again to have 5 subcategories to give your site structure.

If you are changing directory structure for an existing site, be aware that you will likely see your rankings drop as Google tries to figure out the changes. 301 redirects do not pass all the link value, so you may need to do a bit of link building to get back up to your current level.

If it's just a few pages you want to redirect, you could also create a shortcut URL such as "domain.com/primary" that 301 redirects to the full URL ("why/specialists/primary-care") so that you can have a short URL that customers can memorize without sacrificing your site structure.