One thing about the import time. Unfortunately there is no way around the fact that at the number of posts you have it's going to take quite awhile. I did an import a couple of days ago that had about 700,000 posts and it took around 16 hours to import everything.
Going from classic takes quite some time because it has to read and parse every single flat file, so it can be slow going. It's a symptom of the whole flat file thing.
