Magento installs fine, and I can see frontend and backend with no issues. However I noticed there are no theme folders (blank and luma) where they were supposed to be. Blank and luma folders are only found at pub/static/frontend/Magento folder but not in app/design/frontend/Magento.

That is expected in the composer based Magento2 application or if you got the zip. All languages, modules, themes will be under <root>/vendor/magento. So, Blank theme can be found at <root>/vendor/magento/theme-frontend-blank

Set Developer mode on get details from here http://devdocs.magento.com/guides/v2.0/config-guide/cli/config-cli-subcommands-mode.html

Remove comment from magento 2 htaccess file from line number 5 (# SetEnv MAGE_MODE developer).
make memory_limit = 2024mb for local
Enable Cache.