Soda’s alternate tab style and folder icons in the sidebar are what keep me using Soda on and off. Every now and then I try something new. Mostly, however, I use Soda and Spacegray. The included color schemes alone make Spacegray worth installing, IMO.
Lately, the last week at most, I’ve been using itg.flat. It’s a new-ish, flat theme and I’m pretty in love with it. The first commit was made to Github on December 2, 2013, so it’s just a month old. I do wish the “small tabs” were a little smaller, but, I do really like the sidebar folder icons. itg.flat comes with dark and light variations, and includes dark and light color schemes, as well.
itg.flat is being actively updated on Github, too, the last update was eight days ago. Spacegray is very active as well, with an update two days ago, but Soda hasn’t seen an update in about five months.
One screenshot of each theme below. I’m using the Spacegray color scheme, base16-ocean, in each of the screenshots, just because that’s about the only color scheme I use.