If you're already using Vimium, I suggest trying qutebrowser, which takes keyboard accessibility to a whole new level, by making it a first-class feature for the entire browser.

It does basically cut out the mouse, and had a several-days learning curve for me, but after that it's pretty great. Here are some cool features, off the top of my head:

* Python-scriptable, though I haven't figured out how to use this yet.

* Bind javascript bookmarklets to a keyboard shortcut (use :bind with the jseval command)

* Toggle not only javascript, but image loading and a whole slew of other features, with a keyboard macro.

* Vertical tabs.

* All config is adjustable via commands.

* Keyboard macros like "pop tab into a new window", "clone tab", "close all other tabs", etc.

* Text selection using the keyboard.

* Quite similar keyboard dynamics to vim.

It has a built-in ad blocker, and you should run :adblock-update when you first use it.

Another browser which is similar, but which I haven't gotten into as much, is Luakit.