So if I understand correctly you want to order the posts by terms and then by date. There isn’t a way to order posts by term, you can read about this here and in the other urls that this links to. http://wordpress.stackexchange.com/questions/87639/wp-query-orderby-taxonomy-term-value-numeric
The easiest way to accomplish the is to get the terms and then do a new query based with that includes a tax_query for each term.
http://codex.wordpress.org/Function_Reference/get_terms
http://codex.wordpress.org/Class_Reference/WP_Query#Taxonomy_Parameters
