Will I ever reach a level of proficiency where I'm content with my skillset, and would that even be desirable?
incidentally for truly impressive emacs packages check out: gnus, erc, slime, org-mode, tramp, magit, ido, paredit, nxhtml, yasnippet.
It just never would have occurred to me to use Emacs as a video editor (my brain has been conditioned to think of it strictly as a text editor). If that idea had popped in my head then implementing it, relatively speaking, would probably have been less of a challenge than coming up with the actual idea in the first place which requires overcoming my preconceived notions.
In this instance, the idea is far more impressive than the actual code. This demonstrates innovation beyond technical prowess because it added a new way of doing something to a familiar software tool that most people would never have thought of.
Being competent with your skillset is, being content with what you are able to accomplish with your skillset is, but not being content with it - at least not in the areas of software for the foreseeable future.