There are so many themes it’s difficult to choose. Inside of WordPress’ own platform, there are thousands of free themes and plenty of paid themes.
I personally use very few. The one I’m using now on most of my sites, WhosChrisHughes.com included is the Acabado theme.
The reason I’m using it is that it was designed to be FAST. They built it specifically to rank well on search engines and make it good for the user. It doesn’t allow for insane customization like some other themes, so if you are someone who wants to customize every little thing, this won’t be for you.
If you are someone who wants to customize every little detail, I’d recommend using the Divi theme by Elegant Themes.