Welcome to the Q&A Forum

Hi, You said you changed design and deleted some pages. Well i have 2 questions for you, answer and i will give you the solution: 1. when changing design, did you change the url rewrite structure ? You could have lost link juice for inner pages this way. 2. You said you got rid of low quality pages. Did you 404 these pages or you redirected them (301/302). Tell me what you did for those page please. As my previous experience insunates, you lost the link juice to inner pages (by changing url structure) or you have done too many 404 or abused redirects in a way that shows Google your site is unhealthy or down. Happy to helpn and wish you luck!

It may correct itself but I'd redirect and then tell Google what the primary market is for the site (US, Canadian, etc) via Google Webmaster Tools.