We do FEs...and have always sailed sans kids.

We are just big kids at heart.

As for seatings, we have always been seated with other couples (twice we were seated alone though). Our first
Disney cruise we did sail with DH's teenage daughter...they paired us up with another family, that was mom/dad/teenage daughter as well.
Same here with us! I love looking at the door decorations and FEs when delivering!
I have been on six Disney cruises...this will be number 7 (unless we throw in a quick 3-nighter sometime in the next month or two). This will be my 14th cruise overall. We just went on the Ruby Princess three weeks ago. While she was beautiful and we had a wonderful time, she definitely was not a Disney ship (and it was not a Disney cruise!).
Trust me, you will get the hang of these boards soon enough...and then you won't be able to stay away!