You ask what the dividing line is in Orthodoxy between acceptable and unacceptable “beliefs and perspectives”. It’s certainly true that a certain diversity of viewpoints is inevitable among the members of a given religious tradition, and within certain limits the tradition itself makes room for that diversity. In Orthodoxy an important distinction is made between dogmata (“dogmas”), which everyone is obliged to assent to, and theologoumena (“opinions about God”), which may vary from person to person without contradicting or compromising the dogmatic dimension.
You’re absolutely right, of course: most Christians, or at least most Orthodox Christians, disagree with my perennialism; but the disagreement is at the level of “opinion” since what I believe—namely, that the Divine and Uncreated Logos has not limited its saving expression to Jesus of Nazareth—does not deny or contradict what these other Christians (and I too) believe: namely, that this same Logos “came down from Heaven, was incarnate of the Virgin Mary”, etc. In other words, though I may subscribe to more than is claimed in the Creed (and other essential bases of the tradition), I subscribe to no less.
It would be something quite different, however, if I decided, as a matter of conscience or personal conviction, that Jesus was not the Logos incarnate, or that the Trinity was a lie, or that the Resurrection was a hoax. Obviously there are people who have these opinions, and there are indeed certain churches of a liberal bent which tolerate, and even promote, such opinions. Needless to say, the Orthodox Church is not one of them! Indeed the rigor of Orthodoxy, its uncompromising fidelity to ancient tradition, is one of the features that makes it so attractive to me.
You speak of feeling a certain divide between your personal “perception” and what Christianity teaches, and you say you are finding that “parts of the doctrine” conflict with your conviction about what’s right and wrong. This sounds to me like a case of conflicting dogmata and not just personal theologoumena, but I’m afraid I would need to know more precisely what those doctrines, or parts of doctrine, are before I could give you very helpful advice regarding what you might do to resolve the conflict. All I can say at the moment is that resolve it you must, for dogmas are, and should be, non-negotiable.
As for your related question on the subject of “judgment”, this is fairly easily answered. When the Bible teaches us not to judge, the point is that we have no right to say who is saved and who’s not, no right in other words to make claims about the state of someone’s soul or about the underlying substance of his character. On the other hand, Holy Tradition is clearly brimming over with “judgments”, and with criteria for judgment, concerning the way people think and act. Why? Because, like all religions, Christianity teaches that certain thoughts and actions are good for people and certain thoughts and actions are not. Simply put, traditional Christians are intellectual and moral absolutists, not relativists.
Admittedly, “paying attention to what others are doing” can, and no doubt often does, become a convenient excuse for ignoring one’s own faults. Christ speaks of the mote in the neighbor’s eye and the log in one’s own. Christians, like Muslims—and no doubt the zealous faithful of all the orthodox religions—have frequently made the mistake of “hating the sinner because of the sin”. But Blessed Augustine (whom I’m quoting here) immediately adds that it’s just as wrong to “love the sin because of the sinner”. On the contrary, what we have to do, he says, is “love the sinner while hating his sin”; indeed our love for him as a person obliges us to “judge” his thoughts and actions when we can see they are harming him.
This of course raises the question of what exactly constitutes “harm”. Suffice it to say that Christianity (again like every religious tradition) does not limit its “judgments” to what may or may not “directly harm other persons” (your phrase). In fact its key interest is in helping people avoid harming themselves—by advising them, at the level of principle, concerning what is and isn’t good for them spiritually and by teaching them, at the level of practice, certain strategies for overcoming self-destructive thoughts and behaviors.
Perhaps these discriminations and precisions will be of some help to you in your efforts to discern your way forward.