Yes all good points!! :)
Some background - we spend a week each summer all together at a house on the beach so we are used to being together. Yes this is longer and Europe, so will be different...
We thought about a cruise - we have also all cruised together - and talked about it - my family did a Med cruise a few years ago. But they want to really get in and see the sights, which is hard to do from a cruise, especially when my folks are not super mobile. It is all of their first time to Europe - my family will have been 4-5 times by this trip, so I would definitely be the leader. Everyone knows that and is ok with it. Although I know it will be challenging. :)
If we can pull this off, my vision would be maybe renting 2 vrbos nearby each other and splitting that way, since finding places for 14 is about impossible. I figure we would have an activity of the day in the morning that we would do together, then people could do whatever they wanted. We have also done Disneyworld together and I am the militant kind of get-up-and-get-there early one, and they all did well. :) haha. But we won't try to move as a group the whole day, that would be a nightmare.
We would probably split for meals often since you are right, too big a group. I think we would treat it sort of as we are together, but not totally together. But they need me to sort of help with the logistics since they are not too sure about how they would navigate in a foreign country. But I know once we get there they would be fine with it. My parents would probably do the major sites they want, and then spend a lot of time chilling in a piazza. My BIL is always on the go, so he would likely set off exploring. My folks would be about 70 at the time of the trip, but not in great traveling shape. The 6 kids will range from 16-6.
Yes, I do hear all of the warnings and I am heeding them. :) I don;t have a vision like it will be all rosy, I know it will be tough. But I think we will be ok because we will be ok to split up a lot, like if we were on a cruise.
Good points also about making Rome longer. Shoot some other things too but I can't remember!
Funny you say Padua, my friend is from there. :) Also, Germany has to be there since that and Rome are my dads must sees, and this is likely the only trip. My brother really wants to visit Germany. My brother in law really wants Italy, and many people want Rome (we are catholic, so the Vatican is a must for them).
Ok more later! Thanks for the help and keep the suggestions coming. Thanks!!!