For the fire room, yeah, that has been pointed out before and at some point we were even certain that Aurora or Henry (or both) would stumble upon Philip in their dreams.
As for controlling Aurora, I think it is pretty self-explanatory that Cora doesn’t control Aurora at all time – Cora needs to sleep too! 😈 Plus if she was controlled non-stop, she would never come across equally believable since she would definitely be acting differently, more like Cora and not Aurora and they would (especially Mulan) quickly pick up on it.
And Mulan herself – I don’t think Cora is afraid of her or her sword (especially that we saw Snow defeating Mulan and nearly killing her so clearly, the sword isn’t protecting her), she just used her cards and manipulated people – in the end she’s a Queen of Hearts, she doesn’t have to threaten people to kill to have them do what she wants, as she proved so many times.
She simply sent Mulan with Emma and Snow because she knew she was a warrior skilled enough to protect them in their mission and make sure they reach their destination as she didn’t know the last portal was and she REALLY was desperate to find it.
I also believe she killed entire village because she had a plan to follow – make Hook believable and trustworthy – other than that she probably wouldn’t harm a single villager as she didn’t care about them. As it turned out they were absolutely harmless, even as zombies…