Ever heard of a perfect character?
They always win in fights, they're really smart and clever, they're good at everything and generally unbeatable. Everything goes their way.

Now look at the Equis Pact. I don't know how many races, but there are many. Do you really think ALL of them will just give up, and surrender control to a bunch of magical talking horses, some with sno-cones on their foreheads?

There should be legitimate underground movements. Political manuevering to get other races into the decision making process.

But nope.
It's all Equestrians.

The Equestrians have tons of powers from all these races that they control, who they don't try very hard to break the control.
They have really damn good weapons.
They have really damn good shields.
They have really damn good spies.
They have really damn good, well, I'd rather not go on.
They even have a goddess that helps them out.

So, are the Equestrians more like a main character of a story, or a perfect character?