Older posts seemed to point to the Delta and Starwood cards being "easier", but that may not be true anymore. You'll know when you are ready. You seem to have a good plan!
My plan is just to get rid of dead-weight cards and keep the ones that have no annual fees and a potential for growth. That's as much 'plan' as I have. Plus I'm trying not to get a ton of inquiries on my reports since I'm gonna be shopping for a new auto loan in January or February.
However, Amex is REALLY tempting.. especially with Discover approving me.