1. Arrive at the turnstiles by 8:35am
2. Head directly up Main Street, through the Castle, and to Peter Pan’s Flight to collect FASTPASSes. If one member of your group can collect FASTPASSes for the entire group, do so and have them meet up at Step 3: Return time of 9:40am – 10:40am
3. See Enchanted Tales with Belle: 9:05am – 9:25am
4. Ride Journey of the Little Mermaid: 9:30am – 9:45am
5. Visit Ariel’s Grotto: 9:47am – 10am
6. Collect FASTPASSes for Winnie the Pooh at Mickey’s PhilharMagic: Return time of 10:50am – 11:50am
7.Ride Peter Pan’s Flight with FASTPASS: 10:10am – 10:20am
8. Get in line for Be Our Guest Lunch
(These are my thoughts now) If you don't care about the meet and greets that will save you a good 30 minutes, but if you do follow that plan. If you're skipping them, I suggest riding Peter Pan, Little Mermaid, Pooh, Fastpassing Space Mountain, walking over to Frontierland to ride BTMR and Splash, then take the train to Fantasyland and use your Space FPs (tip: use the route behind Barnstormer, it leads you right in front of Space). After that you can do the other rides that don't get high waits or whatever you want.
I would try and hit the classics such as the Haunted Mansion, Pirates, and the Jungle Cruise. Also make sure to catch the Carousel of Progress. Its the only WDW attraction Walt Disney personally rode!
The nice thing about this method is I've found myself in attractions I might not have planned to go to/on, just because my timing was right for when I was walking past.
I start in Tomorrowland, but that's out of habit. Or at a popular character meet and greet...so I haven't sweated myself into non-photogenic oblivion.
Disclaimer: I don't know how busy WDW is in this time of year, and no offense meant to those who love their schedules. Also, I go by myself when I go, so I don't have to worry about appeasing anyone but myself.
Going to the left first and going Jungle Cruise, POTC knock those out before 10am and get fast pass for Splash then Big Thunder back to Splash
Should be done by 11am
Fast Pass for Peter Pan
Then do HM and parts of Fantasyland or Tommorrowland and as Peter Pan is centrally located the return is fairly easy
I prefer knocking out 4 E-tickets early over the Peter Pan centric aspect of attacking Fanyasyland first
As a group of 4 adults, I would make the 'thrill rides' a priority. I would aim to arrive at the parking lot or 'TTC' of MK at least 45 minutes before opening, to allow transfers to the main entrance and complete security checks etc.
After entering the park, I'd generally send one person to head over to Space Mountain to collect fast passes for the group. Then head over to Frontierland and meet the rest of the group. Then I would suggest hitting Splash Mountain and Big Thunder Railroad, after which it may be time for your allotted fastpass time on Space Mountain. Once I have these three done, I generally don't worry about the order of the rest of the attractions (speaking as someone who mostly toured with adults rather than children). After you've hit the 'big 3' the park will probably get busy very quickly. Take it easy for the day, don't try and cram everything in - you are on vacation! Whilst its good to have a basic touring plan, rides can go down and things can go wrong - often the result of not achieving said plan is the precessor of the Disney World 'breakdowns' that you will witness happening later in the day! (That and young children of-course).
I know you are set on using the EMH, but have you considered switching to another day? In my experience, Sundays with EMH were almost always insanely busy. There is an argument that Sunday is 'flight day' and a lot of people leave on Sundays so is an ideal to hit the parks - I personally think this is unfounded as the lack of tourists who have travelled by air, are generally made up by the locals who frequent the parks at weekends.
Regardless of what you do, MK can seem overwhelming to any guest. However, you are a group of adults so perhaps it would be best to prioritise which attractions you would like to do, rather than aim to hit all of them.
Splash Mountain, Big Thunder Mountain Railroad, Haunted Mansion, The Barnstormer,Mickey's Philarmagic, Mad Tea Party ... Those are GREAT.
Everything else I haven't tried or simply thought they were boring or VERY kid friendly (we were adults).