We do use themes and plugins at Copperplate Design. A list of themes we have used or tried plus themes we have rights to:

Theme Application
Anaximander sourced via, and cours
Grepfrut preview
Wisten preview
Barberry [owned] demo
Good Bones demo
Selfy [owned] preview
Valise – Agency Personal Portfolio [owned] preview
360 interesting but slow preview
TwentyTwelve simple core themes Twenty Ten through Twenty Fourteen
Pagelines Pro Using old version
Modern Flat – Admin control panel theme [owned]
Incorporated [owned] preview
BLOQ [owned] preview
Staggerly news theme [owned] preview

We use plugins, too. Here are plugins we use:

Plugin Application
BackWPup data and content backup
QuForm contact, registration, scheduling forms: torreano-depos, shaolinkungfuzen…
Responsive Google Maps [owned] WordPress Business Builder Pack April 2014
Stimmy [owned] mobile menus
Popover popups by wpmudev page popups.,
BugMeBar [owned]
ProVision [owned] email templates (not wordpress)
Lotus mobile theme [owned]
Novatny geometric typeface [owned]
Charlie logo typeface [owned]
Google Maps Generator for WordPress Blogger Bundle 2013
Out Of The Box DropBox plugin for WordPress
Nice Notifications WordPress notification bars
Pure CSS Responsive Pricing Tables
Add From Server
All In One SEO Pack SEO for site and all pages, sitemap, analytics for google&bing
Events Manager with simple customizations:,
Jetpack sharing, Omnisearch, mosaic and carousel, subscriptions, stats, Facebook & Google+ &c, Monitor, Photon (except where bad for masonry)…
Social Media Widget sometimes.
Coming Soon Pro very useful under construction and maintenance pages
WordPress HTTPS SSL page by page
Nav Menu Roles user level access control to menu items:, [see Codepress Menu classes]
Custom Meta Widget smaller and configurable meta for Use Site link
Google Doc Embedder problem is how renders in excerpts and maybe seo
YG-Tag-Cloud Copperplate’s customizing the tag cloud.
Salesforce Plugins: SharedVue Syndication by SharedVue WordPress-to-Lead for Salesforce CRM by Thought Refinery (Plus WP Mailfrom II) using as selected by OOTB at