TYPICALLY, Wednesdays are the slowest day for MK in all seasons. Don't know why, but several Guide Books / Tour Guides have confirmed this.
I agree with hitting it EARLY, doing the real bottle-neck rides & shows, then GET OUT for a few hours. Don't waste time trying to do a character breakfast, or even eating at all -- just hit the 'big ones' and then go on to another park. Returning to MK later is good, but don't expect there to be much room to move, not on a Saturday evening. The desire to see the SPETRO parade ALWAYS causes Saturday night crowds to be almost impossible.
Most people going to AK are tired and done by 2pm or so, thus getting there by 1 or 1:30 should provide less crowds. But remember, AK closes at 5pm most of (or all of) the time, so allow time to see the things you want.