every-emacs-initialization-file VS emacs-config

block-undo. Have keyboard macros undo in a single step (something vi gets right!).

Installing that Embark key series implementation I mentioned above, to get extra actions for key series such binding them to a key or turning them into named keyboard macros.

Generally I recommend to maintain all personal code in the form of tiny but proper Elisp libraries. The config just glues everything together using use-package/setup/your-self-baked-macro. See also /u/oantolin's config which uses this style: https://github.com/oantolin/emacs-config. I cannot recommend this enough!

I have 3720 lines in my configuration. I try to write as much of it as tiny packages that I configure with use-package, just like I do for external packages. (I highly recommend this form of organization) Many of these are only useful to me, but some would be very reasonable to steal, like:

I have a slightly different take on this in my configuration, file shr-heading.el. In addition to imenu support I wanted next and previous heading navigation commands. It turns out you then get imenu support for free, since one way you can specify imenu entries is by providing a "goto previous imenu entry" function.

I wrote a small drag-region package once. You mark a region, turn on drag-region-mode and then your normal motion commands will drag the region along until you turn the minor mode off again. I never tested it with evil.

I'm very happy with ecomplete now, I mostly just need the completion and automatic storing of addresses I write to, as configured in your post. But occasionally I want to remove an address or manually add one, so I wrote a couple of commands to do that which I bind in embark-email-map to + (for adding) and \ (for removing). I don't think I've used these commands directly, always as Embark actions. When I want to add an email to ecomplete I usually have it written in some buffer already. And the command to remove an email I've only ever used from the ecomplete completion interface or from a message buffer after mistakenly having inserted it and realized that's an old address I'll never use again.

I keep some packages in a subdirectory my personal configuration and don't create a separate repo for them. (Also, not every file there is really a package that could be released: some don't follow proper naming conventions, or depend on details of my configuration).