We made it home safe and sound! I'll post more on the trip later, but I wanted to record what worked and didn't for us during the travel portion of our vacation.
Elijah was great on the plane. He didn't sleep very well on the way to Switzerland, even though we gave him a small dose of Benadryl. Despite the lack of sleep, he was happy and relatively laid back. On the trip home he slept about an hour on each of the three legs. He sat on our laps, looked out the window, and played with his toys. We never did pull out the laptop for him which made me very happy. Having new little toys wrapped up to pull out whenever he started getting bored worked great for us.
Unfortunately the busy book didn't get much usage. Eli likes it but the book is much too large for airplane trips. I think it will be great for church and car trips. Luckily my parents only had one carry on bag between them, so my dad ended up carrying the book for me. My next project, or one down the line, will be another busy book for airplane trips - just smaller to fit into luggage better.
The other passengers were great. They were all willing to switch seats so Eric and I could sit together with Elijah (although that could be because they didn't want to sit next to a possibly screaming toddler). On the long ride from Zurich to DC (8 hours) a woman was willing to switch so we had three seats together. Letting Eli have his own seat was great. It allowed us to relax more than if he had always had to be on someone's lap. The flight attendants were also wonderful. I know it's their job, but they were all very friendly and helpful. Eli, of course, charmed them all and one stewardess even took a picture with him.
Having snacks along went well too. Airplane food is better than I remember (even though you only get it on long trips) but Elijah didn't want to eat it so having the crackers and such along kept him from starving. It even lasted through the trip for on the trains and buses.
Also, an umbrella stroller was a godsend. Eli was comfortable in it and it was so easy to collapse when he didn't ride in it. It was easy to tuck away on trains and buses and gate checking went as smoothly as I hoped.
Overall it was a wonderful trip and I am so glad my family go to spend time with Elijah. And of course that Eric's parents got to see Switzerland.
I don't have pictures from the trip yet, but here is the requisite Eli photo.