Do note that this is six addons I couldn't play without. Your opinions may differ; these are mine. None of these are for specific gameplay situations so much as more just for general quality of life in WoW. I'd love to see their features included in the standard UI by Blizzard, but until then, I'll carry on using them. You could give them a try too if you felt like it!
Addon Control Panel
Download Addon Control Panel: WoWInterface, WoWAce, Curse
This nifty addon is top of the list. Why is it top of the list? Because as the name suggests, it's an addon that allows you to control your other addons! It's all very meta. Seriously, though, if you're into addons like me, this is the one addon you should never be without. It allows you, by way of a simple screen, to switch on and off addons and modules of addons at will, without logging out of the game. I honestly don't know why this hasn't been included in the Blizzard interface as standard yet. Addon Control Panel proves it's possible, and it is just such a huge quality of life improvement for anyone who uses addons -- and that's most people.
Filed under: AddOn Spotlight