I've used WoW-Pro for years and in WoD, Legion and now BfA it's been awesome for just going on auto-pilot and working your way through a zone. It has 3 levels of depth you can set, so you can set it to just do 1) the main story, main points of interest and rare mobs and treasure that aren't far off the beaten path; 2) every quest with a more thorough dive into the side stuff; 3) absolutely everything.
Possibly the most complicated Addon I have ever used it is also one of the most powerful. You can build custom Visual and Audio warnings for virtually any situation in the Game. I have used it for Buff Stacks Low HP and Ability Cooldowns many times over the years on various Characters. Blizzard added similar Visual Warnings in Cataclysm.Git Repository: https://github.com/Geigerkind/ModifiedPowerAuras
Anyway I will go ahead & download the Twitch app like everyone's saying, but I still need to know whether my in-game addon settings will carry over automatically, or whether they'd return to default same as if they'd all been uninstalled in the curse client then reinstalled from scratch. Because if it's the latter then I will have to take screenshots of the settings on all my toons BEFORE I install the addons thru the Twitch client.