Need to kill off a few Websites

I work for a company that own 7 large scale websites. Problem is they have been sharing the same content between the 7 for the past couple of years (dupe content issues).

So on any given day one site could be cannibalizing the rankings from another. Well we want to start consolidating into one large website. So I have taken measurements that include
Google Analytics Numbers
Indexed Page Count
Backlink Count
Alexa Ranks
and more

What other metrics should I be looking into? Also which one should go first? I mean what factors are more important when making this decision.

Do all the websites share the same CMS (inc databases) or do they each have their own CMS and databases? If each has it’s own CMS are they different CMSs or are they copies of the same CMS.

Will the consolidated site use one of the existing URLs or is it a new URL? Any content that is moving URL permantly you should consider the use of the 301 HTTP status code.

Each one is independent of the other. They all have their own servers and databases. The URLs are different for the most part. Although some share the same structure.

And of Course we will be implementing 301 redirects. Fom one site to the main website. But how do I go about choosing which one to kill off first. You know a trial run?

Does one of the sites consistently rank lower then the other sites, if so I would target that one as the first to redirect?