Even if you get a theme full of features and options, there may be something you need that is missing. The web is everywhere and even the more perspicacious developer will not be able to fulfill every need of every user, and probably this wouldn’t be possible.
The flexibility of our themes allows for various modulations, and an experienced user can make the best out of it. But who can afford losing customization because of a theme update? And who can afford not to update a Theme or even the platform itself?
A lot of people claiming that there is no need to use a Child Theme because WordPress is considered to be a “safe” platform and won’t easily “break.” Although it’s rather robust comparing to other CMS, we shouldn’t forget you’re dealing with code and as any people’s creation is far from perfect.
So, to keep up with your work, use a Child Theme. Always keep a backup of your website before updating, now it’s easier than ever. And get spoiled.