I assume you have already looked at the deck plans and pictures on Carnival's website. I have never been on the Miracle, but all the options you mentioned for cabins look fantastic, I don't know how you could go wrong with any of them.
I'm not sure I would enjoy that long cross Pacific journey. I prefer to fly to Hawaii and cruise the islands instead of spending so much time in open ocean, but it would be some wonderful family time.
I think Carnival books 18 months in advance, so you should be able to use that as your guideline, but do as Pete suggests and turn that problem over to a good cruise agent. They should know those specific times and may have more chance of getting those preferred suites for you.