I created shortcuts for a basic HTML5 skeleton layout (with Emmet installed you just type “!” and hit tab) that includes basic features for SEO and accessibility: title, meta description, meta keywords, a canonical link, semantic elements, WAI roles etc.
Additionally features shortcuts for things I always forget (how exactly to code a click-to-call link) and images feature placeholder alt=“” attributes.
The customizations included here are between lines 594 and 760.
On my system the path to the file is: /Users/matchbox/Library/Application Support/Sublime Text 2/Packages/Emmet/emmet
...although you might need to escape those spaces, not really sure.