As someone that has topped 300lbs in the past let me tell you all about the problems that causes.
Tube slides I had to stop doing for a time as half my rides I flipped over and ended up on my stomach or back. It is the momentum and hydroplaning with increased speed, plus I didn’t fit down in the tube as well so the center of gravity is higher. Maybe someone 375 or more could complete the barrel roll on a tube slide but I couldn’t and would just crash down. Gets a little Acton Parky. If you do flip make sure to flip over to your back, I banged myself up a bit entering a splash pool on my stomach once. There was one slide at Zoombezie Bay if I managed to stay on the tube I would plane across the splash down pool and get beached on the concrete. Fun and the kids loved watching it but probably not the safest thing.
Mat racers. A bit of airtime is fine but I would get so much I was landing more on the horizontal section. Absolutely brutal on the chest and knees to do that 2 or 3 times on my way down.