Misunderstanding of what the game is
Hi original poster,
Please re-read other replies here and reflect. Other people have posted valid responses to the problems that you are having and some of your replies show that you have not actually gone back into the game and re-tested things to learn. The most obvious is your reply about tank enmity. A tank with stance on who has used provoke once (and once again, after dying, if applicable) will never, never lose enmity to a healer, even if that tank is just pressing their 1, 2, 3 rotation over and over. Square Enix has developed the game specifically to guarantee that, so that players don't have to argue about enmity management.
The other debates are similar but since there are so many healer options it gets complicated, but the short version is that you have fundamentally misunderstood many mechanics of the game.
It is not fair to demand that the developers change content because you are unwilling to learn. If you open the game, go back to a training dummy with whoever played tank, and test some of these things that posters have mentioned, you will learn that your assumptions have been incorrect, and what you learn will allow you to clear that boss.
I don't post this to be mean, but because I enjoy the Dawntrail normal mode content a lot; it is a huge improvement, and myself and all of my friends that I have asked are very positive about it compared to previous content, and I don't want to lose these improvements over invalid feedback.
If you aren't willing to think creatively and spend 15 minutes testing things on a training dummy then please do not ask the developers to make changes that will make other players bored and unhappy. If that commitment is too much, then this is not the right game for you (and nor would be any MMO)