I would say just plan and realize this is not a normal family trip. 10 adults and 10 kids is crazy (I am an only child). But it can still be a good trip and family experience. Just don't consider it a trip to
Disneyland.
One year we were going to DL (we live 6 hours away) to meet up with friends of my DH from Iowa who have girls our girls' age. Sounds like a great plan. We were doing SOCAL together. San Diego Zoo, etc.
All of a sudden my DH's brother's family from the south was going to be there because their son was at USC. Totally unplanned we discovered we were going to be at DL the same day. How crazy is that? It was parents weekend or something. Now, we love spending time with them and my girls adore their Aunt, Uncle and teen cousins. We had met them at DL before when they were checking out USC. It was our DD now 9s first trip to DL.
How the heck do you balance touring? I finally decided this was not really a trip to DL... it was two odd reunions in a very public place. We were bouncing between parks like a dude trying to balance two prom dates.
Here is how the morning went - started at DCA, spent the first two hours in the Burr-bank ice cream place and shopping at Greeting from California. I HATE shopping and every ounce of DISer in me could not handle wasting key touring time. Then, somehow, when going to get FPs for TofT... (TofT was new at DCA) ended up on the the ride. Now understand that I like thrill rides - but have been stuck on elevators 5 times - one time requiring maintence to get us out. While I wanted to ride TofT... I wanted to "warm up" with a fun ride on Soarin' and/or California Screamin'.
The standby line was 10 minutes and the other DH (who I really did not know) said "let's go." He and his 6 year old had gone on TofT 6 times one day at WDW. My DH does not like thrill rides but does not have my irrational fear of heights or elevators. I could tell he did not want the drop. I said I would go. So it was a guy I did not know with his 6-year-old, me and my 5 year old who was barely tall enough.
Did I mention my then DD5 was afraid of POTC?????? Why the heck was she all of a sudden okay with TofT???? Talk about pier pressure. All of a sudden this 6-year-old she barely knew said it was fun...
While in line the friend of my husband kept talking to me. I was so darn nervous I just wanted him to shut up. I had no desire to be on Tower of Terror at that point of my life. I finally told him to shut up. Seriously, I think I said "just stop talking to me" at some point in the boiler room. It was akward... but he didn't say much after that.
We rode and my 5-year-old claimed to love it and wanted to go again. I said no and we moved on.
At the end of the night we have a picture of my DH with a sleeping 3-year-old on his shoulder in the Toy Story ride. He looks pale and has a vacant stare. I recall visiting with our out of town family on Main Street following the parade and my DH having our youngest sleeping on his shoulder.
As a DISer - I look back on the trip it was a TOTAL disaster. But really, it was a nice visit with two different groups of people in a kind of stressful place.
If we had never been to DL - it would have been horrible. But we were DL vets.
I would strongly suggest you look at this as an opportunity to show the newbies a good time. Make the focus them. If the focus is helping them have a good experience vs pleasing everyone - you should succeed.