Some other browsers that support vertical tabs allow you to have the tabs on the right side of the screen. so may websites have their navigation system on the left, so having that stacked with my tabs can look dense and make it hard to find what I'm looking for, the right side is usually pretty free and empty.
The settings option for tabs would be split from vertical to vertical (left) and vertical (right), the tab system would be the exact same for the right version except that they are on the other side. The zen browser that I use when on windows supports this.