> 0. On startup, Emacs still appears to block while  loading the gpg bits for the various archives.
>
> 1. Even though installs happen asynchronously, there is a large amount of chatter in the Messages area -- can that be silenced?

Thanks for the comments, I'll look into improving these points

> 2. This is a admittedly a special case: For many years, my emacs-startup file is called emacs-startup.el and is versioned by git -- ~!/.emacs is a symlink.
>
> The code in package.el that adds the (package-initialize) to the top  of the startup file appears to go open the startup file each  time to  check if its magic cookie is present at the top -- so in my case, each package update caused the yes/no prompt -- perhaps remember that the cookie is added via a lisp var (hopefully customizable by the user)

Technically this is unrelated to the async feature, but it looks like a serious issue. What yes/no prompt are you talking about?