The joinning ritual is also one of those "it can be viewed as blood magic" rituals. And Adralla can have tested her spell in a myriad different ways. It may have been entirely based on field testing. She may have taken a lucky guess. We will never know.
I personally wouldn't want to go into battle against a blood mage with a spell to prevent mind domination if it was only passed as "I hope it works because it's never been tested".
So basically you dislike Orlais for being a powerful nation, which will consume the lesser nations around it?
And no, I don't dislike Orlais because it has the heart of the chantry in it. Let me try to be as rationale, without emotions as possible with this as for the reasons I don't like Orlais. And I will attempt to keep the Chantry out of the argument as much as possible. They won't be gone entirely but that's because the Orlesians and the Chantry work together so often, and their interests commonly coincide.
Orlais is an empire where the nobles play petty games, just like any other country, medieval, in-game, or modern. They use bards and assassins to to manipulate events in their favor or to assassinate their political opponents. Again, this applies to every nation. What makes Orlais different is that the royal family only rose to power with the endorsement of the Chantry, and now the nobles were constantly seeking the approval of the current Emperor/Empress.
But their sovereign lord/lady obviously does not have nearly as much power over them as say England's King during the dark ages. King Alistair mentions this when he says that several nobles want their lost province back. Celene is advocating for peace, but Teagan is doubtful of there being any. This shows that the nobles are more than willing to ignore their queen to go out and conquer Fereldan.
Now I'm aware that the nobles in Fereldan did the same thing during Origins when Anora called for the fighting to stop and it took Eamon and a landsmeet to make it happen. But in Fereldan and the Free Marches (which I assume is similar to the other city-states based on Kirkwall), is that even the nobles fall under the law. Aveline's guards raided the Du Pui manor. The Templars went to those Orlesians in Act 3 whose son was actually a complete idiot.
If the templars knew she was shielding her son from them, they would fall under the same justice of the templars as the commoner who allowed her cousin some food and rest. We know this because her husband is concerned about that fact.
There is still corruption like the insane magistrate's son constantly getting off the hook for killing elves.
But in Orlais, nobles and chevaliers are allowed to rape any woman, not just elves in the alienage (which is a horrid act in and of itself) from the middle and lower class. Human, dwarven, elven, it doesn't matter. Then there's the expansionism, constantly working with the Chantry to help spread the Chant of Light to all four corners of the world. Through force of arms and bloodshed.
Of course Orlais would help the Chantry with that, it increases their own power in the world. And if that means helping the Chantry destroy the heathens, like the Dalish elves who helped Andraste in the war against the Imperium...well that just means more land for the nobles to bicker over and more elven slaves to buy and sell. They committed genocide for power.
If you can't tell, I just don't like politics no matter the country. The difference between Orlais's expansionism policies and Calanhad's in Fereldan was that Calanhad originally was fighting for the honor of his fallen Lord. Once the invading force that killed him saw his honor, they were so impressed they swore fealty to Calanhad and things just snowballed. Orlais deliberately conquers others, much like Tevinter once did. Orlais still slaughters thousands of people for their own religous and political power, while Tevinter slaughtered thousands of people for their magical and political power.
Fenris states that the one time an Archon made slavery illegal, he was slaughtered mercilessly by the other magisters. Slavery has been part of Tevinter for so long that they don't know how to act without it.
The Chantry has been part of Orlais from the beginning, and with their long history of expansionism and genocide of anyone who doesn't share their religious beliefs, they don't know how to act without that either. That is shown with evidence with Mother Petrice and the Qunari and the templars threatening the Dalish elves on Sundermount to convert, when all they were doing was waiting for a sister clan to give them some more halla (I heard that in a random comment from one of the elves).
And yes, those examples were the Chantry, but the Chantry and Orlais are so interlinked together that I have a hard time seeing Orlais not doing that either.