Unicorns/Alicorns have access to magic for restraining naughty ponies as well as spells to conjure up impliments.

Earth Ponies have the physical prowess to effectively restrain, and control over their strength is reflexive. Plus I imagine the more sturdy of the three are better suited for establishing dominance.

Pegasi have wings. They go everywhere with sturdy, improv corrective impliments while keeping their legs free in case the naughty pony squirms.

Thoughts?

Unicorns/Alicorns definitely. They don't have the physical limitations that using hooves does. This lets them spank much harder without even holding a tool for spanking. It can also be used to more easily trap the spankee in place.

6643643

All the best scenes I’ve written are with Uni/Alicorn doms. Nothing beats the versatility of magic.

Unicorns. They can hit the spankee from all possible angles.

6643643
I think the increased physical strength of earth ponies is cancelled out by the fact that they can't use all 4 of their legs. After all they need one to spank with. Unicorns can hold the spankee down with all 4. Also holding down a spankee is much more about position and leverage than physical strength.

Yeah, Alicorns/Unicorns, without a doubt.

I have to agree with the crowd here - not many creatures who can deliver a spanking as a ranged attack.