Most of our trips have been with a wide range of ages.. While we try to do some family things, including some meals as a group, most park touring has been with smaller groups. That way, we accomodate almost everyone's wants and likes. DW is their companion, advisor, and (...their parents don't know), their bank, for shopping.
I can get everyone on their "Must do's"....And when small groups of DGK's can't agree on what to do next, I can usually mediate and implement a plan to accomodate everyone...
While they are becoming even more expensive, Character Meals are a great family event....we have tried to do several on most trips...usually at least one dinner, and one breakfast...

We have seen it from both sides...two of our earliest trips were with DMiL and DFiL...and we did most things as a group...even then, our kids are spread over 11 years, and had varying tastes, and attention span....But rather than slow down to stay together all the time, we created rendezvous points, to allow the older DK's (and me) to ride our favorites, while always giving the in-laws the option to join the group, or to just chill.

DMiL and DD#2 rode and re-rode "If You Had Wings", while DS#1, DD#1, DFiL, and I rode the Turnpike again and again...but we all did PoTC together...DW shopped...but joined us on IASW and Peter Pan...shopped again while DFiL and I took DS#1 and DD#1 on 20,000 Leagues...

Those two trips were special for the In Laws...One of very few vacations they took together...The way we did it helped to make it special. I still remember hundreds of special moments from those trips. Now that we are the Seniors in the group (actually older than they were on those trips), we enjoy the lack of pressure to do it all together, while enjoying the special moments of individual and family events.

Never had a bad trip...never insisted that we stay together constantly...