Thanks for the responses. I also had a guy who rents an Ideal SS text me that “There's room for 2 people to be seated at the back of the motorhome while traveling.” So, I’m guessing one passenger sits in the middle and the other behind the passenger.
Some other post showed lap belts, but no shoulder belts, so it’s probably not safe to sit behind the fridge even if you could.
I think the slide out adds 600 lbs. The photo of the door sticker states that the OCCC is 886 lbs and the GVWR is 8,550. Thus, it appears there is only 886 lbs left for passengers, gear, and water. I calculated that the water tank could weigh 250 lbs, so maybe only 636 lbs left for passengers and gear. My wife and I weigh a combined 340 lbs, so 296 lbs for gear could work. My whole family weighs 580 lbs, so only 56 lbs for gear, which might only be enough for a day trip or possibly an overnight. So if traveling with the whole family I would probably need to leave the water tank near empty and fill it up at the campsite.
The slideout seems like a good idea, but with these Class B’s everything you gain means you lose something else. I dunno. Maybe the SS Agile would be better. (My driveway is exactly 20’5” from the house to the curb, so definitely looking for something under 20’)