4216 is a big motor, deffinitely not right.
By using 8 inch props @ 3S, I would say it's gonna be something like 2208/2210 with kv values around 1000/1500
I mentioned that forced landing is more of a risk in some cases since some pilots dont understand that even though forced landing once kicked in cannot be canceled but still increasing throttle will still get the drone up and it may still fly...