If you want to be in the front of the SDD line and not wait a long time, you are going to need to get to the park very early and be in the rope drop crowd. I just got back and I wouldn’t call the parks crowded and arrived right at 8:55 and had a 75 minute wait for SDD. it was worth it in my opinion - great new ride. If you have any hope of getting a FP for SDD, it would be on a later day of your stay. I was there for 8 nights and did my FP reservations right at 60 days but there were no more FP available for the day I wanted to go to HS.
It is easier to get the FP for Toy Story Mania or Alien Swirling Saucers.
The land is fun and I think young kids will love it. I had FP for ToT and RnRC and TSM. Skipped the swirling saucers. We were done in the park with eating lunch and doing Star Tours and the 75 minute wait by 2:00 and left. I would try to use the FP for HS and then take my chances at Animal Kingdom later as it may thin out towards end of day.