Its not 3rd party - but you really should look into the Sitecore Experience Accelerator - while it doesn't have "controls" in the way you are thinking, it comes with a number of components/renderings that you can use to build pages and then you can build your theme to style those components.
It is also very easy to build other components that you can use with SXA that follow the pattern.
This way you have a nice standardized set of components, that all follow a good Sitecore architecture, you have a lot of built in additions like Sitemap, Robots.txt, Redirects etc... Boiler plate stuff that you would normally have to build yourself. It really does save a lot of effort in the build.
Also, you don't have to think too much about the information architecture, as there is already a good pattern to follow.