I usually remap the control keys to act as a modifier for Unicode characters (as Caps and Enter are my "Control" keys) but that's not much. I need more keys.

I have 2 keys to switch to the next/previous tab, in browsers, consoles and programming environments- the same keys can switch virtual desktop with a modifier.

I also have a key to invert my screen (black on white vs white on black), a key to either switch to a terminal doing a ssh to a specific server or spawn a terminal and start that ssh, etc.

It takes some time but offer greater productivity. I dislike the ticking of mechanical keyboard, and I really prefer "chiclets" keyboard as they generally require less force to be applied, but I would consider a mechanical keyboard if only for the extra keys.