I doubt you'll have any problem getting those. Akershus and Crystal Palace can be a little more difficult if you're trying for the 8:05am breakfast slot OR timing things up for dinner before evening things (i.e. MSEP, Illuminations, Wishes, etc.), but you should still be good booking those on day 180. I mean, I booked the 8:05a for Crystal Palace a couple of months ago...party of 9...no problem. I also don't see any issues with Sci Fi; however, DHS "sometimes" experiences an influx of people for dinner in Dec simply due to Osborne Lights. While I had to turn our last trip upside down and then sideways b/c of Be Our Guest, I remember on day 180/6am being floored that I couldn't get the 6pm at 50s Primetime. I was stuck with either 6:25p or 5:35p. We ended up switching days and after much stalking, I got a 4pm which was perfect for seeing the lighting of Osborne Lights, but still.
Good luck!!!!