These are my plans. Note that I have one early entry to use. It is offered 2 of my 4 days there and not offered the other 2 of my 4. Note that when we do DCA, we will be starting off the day in DL. 8 am is 10 for us.
If Nemo is an early entry ride.
We're going to do the fantasyland rides as usual with the possible exception that if someone reports a spillover effect at the Matterhorn on their trip, I may bump that up a spot. Nemo is a 15 minute ride and will eat up a huge chunk of time. Dumbo and PP are likely to be building by then. Also, it would be more shoe leather to get back to Fantasyland. And there aren't many Tomorrowland attractions open during EE that build long lines and don't use fastpass.
The plan is to hit Nemo first on a day that has no early entry. We'll probably want to ride it again so we'll probably hit it first on both days with no early entry.
On the day where there is early entry, But we can't use it, we're going to hang out on the Frontierland,Adventurland, New Orleans Square, side of the park when we get in.
How would this change if Nemo is not an EE ride?
Well not at all. I would still hit Nemo on a day early entry wasn't offered at all. This would be because even though Nemo wouldn't be operating, a lot of people with early entry would be lining up prior to its opening, while I'm still at the main gate. I'd be behind all of them.
What would I do if I had multiple early entry days to use?
By all means I'd probably do the fantasyland stuff on one of my early entry days and nemo and the tomorrowland stuff on the other.