[Ziomislaw]

Not familliar with SpaceVim (yet) so I can only speak for Spacemacs. Emacs has really bad support for writing modular code (~/.emacs/init.el), and Spacemacs adresses this issue. Also a lot of work went into integrating various packages and modernizing emacs experience. To give an example, Spacemacs out of the box had 90% of features that my custom-crafted ~2kloc config file did. And I find the (new) shortcuts so intuitive that I am considering adding them to my vimrc.

> No runtime,

Spacemacs loads your config (very fast I might add), adds a nice startup screen, gathers statistics about your config etc.

> no package manager

It also bundles use-package - which is a package manager. And makes bootstrapping emacs on a new machine trivial.

> no changes to the actual binaries of either app

Remember this is emacs. You don't need to rewrite any part of it, you can change anything with advices/hooks, and it is actually easier to do than patching some random packages.