There isn’t much benefit to staying on-site. I’ve done a lot of hand-wringing on that topic.
We recently did our trip-of-the-lifetime, long-postponed Disney World trip. Pre-lockdown I thought the on-site perks were worthwhile. So, even though they seemed mostly gone now, I had reservations for totally on-site, totally off-site, a mix of both and totally off-site with tent reservations for on-site benefits. All fully refundable until shortly before the trip. When it reached the decision point, even though on-site didn’t seem worthwhile, I went with the off-site with tent reservations.
We had a similar trip to what you are planning (except less people) in that we were there for two weeks 10-day tickets and didn’t stay all day every day.
Mid-trip I cancelled the on-site part and changed to entirely off-site for the last week. It really wasn’t worth it for us. We drove to FL, so had a car and after a few days I was soooo over Disney transport, so we were driving everywhere we could anyway.
Also, for a lot of people, a big house off-site is really the way to go. With AirBnB/VRBO, the price doesn’t go up that much as they get bigger. So, a 6-bedroom house with pool cost only a bit more than the 3-bedroom condo we got. We chose the condo because it was just the three of us and condos were closer to the pool/slide.
For that many people, you can have the best of both worlds by doing what I did. I added one or two night tent reservations into the plans. Tent sites allow up to 10-people (so onsite benefits), don’t charge for parking and also get free parking at the parks.
So, let’s say that your park days are Sun/Mon/Tues and Thurs/Fri. You could reserve a tent site for two-nights Sunday and then one-night on Thurs. Cost will be $300-ish. If you have only one car, then subtract off the $125 for 5 days of parks parking. If you have a car anyway, Disney will charge you parking either with the hotel stay or at the parking lot, with the exception of the campsites. So, then you can calculate how much on-site benefits cost you per-person per day. Assuming only one car and 7 people, onsite benefits would cost $5 per person per day. With more cars and more people that goes down even more.
What I did with the one-night tent reservations, was to put that we’d arrive at 11 pm and I put in no site requests. So, that meant we got whatever was left at the end of the night which is fine since we didn’t really use it. If HoopDeDoo had opened before our trip we would have parked on the site when we went to that.
If you look at the houses near Disney, you’ll see some common features. Like the garage will be turned into a game room. This is because they can’t hand out garage door remotes, so it can’t be used as a garage. Another is that the pool heat only works between X and Y time. That is because each house doesn’t have a heater in a lot of these developments, and the times are centrally controlled. There must be exceptions to this, but I saw that a lot.
We stayed in Windsor Hills and it was amazing! For anyone looking for a 3-bedroom near the pool with a Star Wars theme, I have one to recommend.
One thing I liked about off-site was that when we went out to eat, it was for a reason. When we just wanted to make our tummies happy, we grabbed something at the condo from the real fridge. I remember one time we were sitting around the condo for our afternoon break. I was eating a Reeses Klondike Ice Cream bar, and I said, “I feel sorry for the poor suckers in hotel rooms.” The family agreed.