Is there a list of testing objectives that an automated test would look to achieve? Is that list vastly different than what is done manually? I like the notion of a "verified badge" but the precise "why(s)" it is awarded should be transparently discussed. In many ways the themes that populate the WordPress "marketplace" inherit valuable brand chi along the line of the old Goodhousekeeping seal of approval. Nothing in the new process should be allowed to result in releases that devalue that (extremely valuable) WordPress brand chi.

Manually testing each theme (or plugin for that matter) does seem somewhat archaic- if that is actually what is happening. Most software development organizations could not survive/scale/produce/innovate varietal products without some "deeply" integrated testing automation. Especially one so large as the WordPress village/tribe/Cabala of software professionals.

As far as aesthetics go, beauty is in the eye of the beholder and should be left that way as much as practicality will allow. If code is poetry then certainly themes are art. As long as the "rules" are followed underneath who can judge what is art? Maybe golden ratio or some color ethics applied generously...

In the end, the market will judge the themes and plugins, so they will either live or die. As long as bad code is filtered out of the marketplace and there is a strong reward/incentive for theme developers to make great themes everything should cruise harmonically. Speed and efficiency will help make more shiny themes and keep everyone feeling special while pressing and coding. Nirvana!