We had a Fiat Multipla for a few years, only 6 seats rather than 7, but it served us well as had three full seats in the back and plenty of leg space.
Had a Zafira which was very cramped.
Had a Chrysler Voyager for a while, heavy on the fuel but a great workhorse. Boot similar to size of the Galaxy and had sliding doors but parts harder to get and more expensive than a lot of other cars, there is the option of the longer Grand Voyager also.
Had an older Toyota Previa for a year while looking for our next car, only advantage to that was the 8th seat! Very thirsty etc but I don't know what a newer one in good condition would be like.
Currently on our second Ford Galaxy. Reasonable boot but it has masses of space inside, especially as seats fold down well when needed. We were looking for a car to accommodate four children, three are now teenagers so needed plenty of leg and head space and the Galaxy delivers. For luggage you might want a roof box or you can put one seat down and still have enough seats for the family. Only thing I miss is not having the sliding door the Voyager had and our Galaxy doesn't have a sunroof 😪
Have hired an Hyundai i800 a couple of times. Great 8-seater, but it is not good on fuel economy and is essentially a van with seats in, has a very nice inside, shame about the outside van look though.
We have tried a LOT of cars out for space over the last 20 years and you have to consider the head space in the back of smaller 7 seaters (essentially 5+2s), it does not take long for children to grow out of the tiny back seats, they are basically designed for children, not adults. We have tried some out and didn't even test drive them as they were so small the boys couldn't even get in the back!