CDN locations for US eyeball networks

Hello NANOGers. I am in the process of scouting for CDN node locations for content delivery to end users in the US. Currently looking at Seattle, Los Angeles, Dallas, Chicago, Miami and New York. Would much appreciate any recommendations, best practices or advice on how/where to get good connectivity to the large eyeball networks. Being small fish, connectivity will be based on the transit I can score or in general connectivity that DCs/server providers offer in the locations chosen. John