I have a similar extension on my motorcycle trailer that is plywood. It is useful for putting anything in the trailer with small wheels like the portable genny etc.
No issue with the motorcycle or ZTR mower.
Have thought about doing it on the Cyclone only because I could make it long enough to decrease the loading angle a bit. That would be beneficial for when the trailer is leveled a bit high in the rear. The ramp extension would make the transition from road to ramp less of a gap.
The cost of the 1/8 or 3/16" diamond plate is holding me off.