I doing SEO for a large site (20+ pages). What are the best practices in regards to the sub-pages of the site? Should I put keywords for sub-pages, and if yes how similar can they be to my home page keywords? What about description and page title, how long should those be and how similar to the home page? Is there anything else that can be done for SEO optimization?

I recommend that you go to http://www.websitegrader.com to check details like title length, meta tags…

It doesn’t really matter what keywords you use for subpages as long as your page is optimized for them and your content is a match.

As long as you build backlinks to your site and subpages, you’l be going in the right direction!