Even with EE happening (which we won't have), should we try to go to Hagrids first? I figured the line may be long because of EE first thing, so that's why I was thinking we should wait.
We don't know which park with have EE yet - but it's likely it will be IOA.
With what you are trying to accomplish, maybe not. You'll get the shortest waits on Hagrid's either riding it first or last. First hour or last hour.
If you ride it first, it could put you behind in trying to get everything else done. If you save it for last, you can get a jump on the crowds at the other rides, but risk the ride going down.
I can see two different plans depending on which park you want to hit first. Also depends on park hours, which we don't know yet. My thoughts were to include all of the 'big' rides and avoid a lot of time wasting by limiting backtracking and walking between parks rather than riding the Hogwart's Express.
1. USF first: Go back to front - ride Gringott's, MIB, Mummy, Transformers, and Rip Ride. Walk to IOA. Tour clockwise. Ride Hulk, Spiderman, Kong, Velocicoaster, Forbidden Journey, Hagrid's.
2. IOA first: back to front, counter clockwise - Hagrid's, FJ, Velocicoaster, Kong, Spiderman, Hulk. Walk to IOA and work front to back - Rip Ride, Transformers, Mummy, MIB, Gringott's.
Pros/Cons:
Plan 1 helps avoid the EE park in the morning.
Plan 1 gives you the best opportunity to ride the 'best' rides (Hagrid's (assuming it's open and you get one ride), Velocicoaster, FJ) multiple times
Plan 2 may put you near an HP area at lunch. Plan 1 would not
Plan 2 gets the 'most likely to have downtime' rides out of the way early (Hagrid's and Velocicoaster).
Use Single Rider where possible. I'd use Standby for any of the 2-seat rides (Hulk, Velocicoaster, Hagrid's, Rip Ride). To me, those are always a gamble.