AK is definitely worthwhile for EE, but of the 4 parks it is the one that probably requires the most thought beforehand. As others have suggested, the turnstiles open at 8:00 on the dot. This often creates a zoo-like atmosphere (pun intended) at the entrance, both because everyone has been gathering with nowhere to go and because the entrance area is probably a little bit smaller than at the other 3 parks. We have also had to wait even to get in the parking lot until not long before 8:00.
When you arrive, it will look like a huge mob, but looks can be deceiving. Everyone is waiting in a relatively small space, but when you go in the park it will not seem that crowded. When you arrive, you should have a definite idea of where you want to go and head straight for it. I agree with those who have said that the safari is great early in the morning, even though everyone goes there first. One of our best safari experiences was last September at EE because the animals were very active and plentiful at that time of morning. If you want to avoid the safari for your first attraction, however, I would suggest sending one of your group there at opening to get Fastpasses for later in the morning.
We typically go to EE at AK and can do pretty much everything we want by early afternoon. At a minimum, this usually includes the safari, the Tree of Life, It's Tough to Be a Bug, the Lion King show (never miss it!), Dinosaur, the Boneyard for the kids, Primeval Whirl, breakfast at Donald's, and general wandering around to appreciate the flora and fauna. After hitting the safari and It's Tough to Be a Bug before 9:00, we usually plan the rest of our morning around the seating time for the Lion King show. If we eliminate Donald's, we can do everything even more quickly wihout feeling rushed at all.
Hope your DH enjoys his birthday!