Thanks, sounds like a good approach! Why would you choose an openback headphone?
I would use a few options when mixing and cross checking on all those speakers. So I would have a pair of desktop computer speakers of about 100 bucks. A good pair of monitors like the Adams or similar and a great openback headphone. It's true if it sounds good on crappy speakers, it will usually sound good on your monitors. Although monitors can help you find the detailed problems better.
If your looking for good monitors you can check this link, it's a pretty good guide too:http://getinstrumental.com/best-studio-monitor-speakers/
Hope that helps...