We shared some of your same concerns during our recent TT purchase also... I have 2 kids boy -7 and girl -5, and currently they really don't care where they sleep, but if friends come or when they get older we thought some way for them to have their own space could be good.
We chose the Flagstaff 831 KRSS or (Kid Room Super Slide), it has a couch in the back with tv and entertainment / clothes dresser. The couch folds out into a very nice and comfortable queen size air matress, and there is a swing bunk on top. We also have the normal couch in front of the camper with the fold out as well (same air matress). This gives us plenty of leg room when not sleeping. We felt the Jack and Jill as you described would be "in the way" when we were entertaining etc...
This config will sleep 6 adults + kid on dinette, or swing bunk + still room on floor for sleeping bags or additional air matresses. We also worried about having to make the beds, but it is not an issue as the air matresses can stay made while folded up, and there is a huge pull out storage under each couch which holds pillows and extra bedding.
Hope this helps. Frank