Spacemacs is an improvement, however I think it the biggest advantage it (and any other modern text editor) has over Emacs is the on-boarding process and general beginner friendliness.
Beyond that, Atom's modes for front-end web development are pretty top notch. We have js2-mode, and web-mode in Emacs, but the overall experience in Atom is often superior. For example, it's extremely easy to quickly install a color-picker, pull open a CSS file, and use a color wheel to make a hex value slightly darker. More, the color-picker UI feels tightly integrated into the editor.
On the surface, this feels trite, however the slow build-up of user friendly developer conveniences adds up.
The general command over the entire environment continues to draw me back to Emacs. Still, I continue to watch for when Atom can achieve this.
Why would a spacemacs user switch to atom? Does it have any advantages?