The reason why I prefer themes from WordPress.org is that they are carefully reviewed by a volunteer staff and experienced WordPress admins, and they are guaranteed to be free from bad code that does evil things to your site.
They are 100% free, and you can often find support on the themes WordPress.org forums. All themes are 100% GPL compatible which means that you don’t have to worry when making changes to your theme.
The themes comes without plugins, so that you don’t loose all your functionality when you switch themes. Many themes have support for the most popular plugins and can recommend plugins that work well with the theme and even help you install those plugins.
There are currently 26 themes that are tagged accessibility-ready in the official WordPress theme repository. This includes the default themes Twentythirteen, Twentyfourteen and the newest Twentyfifteen and 3 of my own themes. That’s not a whole lot, considering that about 3 to 7 new themes are approved and added each day.
And that’s what needs to change.
-To find the themes from inside your WordPress installation, go to Appearance, Themes, press Add New, and open the Feature Filter. Check the Accessibility Ready box in the Features column, and then Apply Filters. You can now preview and install your theme.
-To find the themes on WordPress.org, go to Themes and find the link check out our new filter and tag interface. Check the accessibility-ready box in the Features column, then press the Find Themes button and the themes will be listed below the form.