>problems that you personally have
So I won't dwell too much on wrong beliefs in general, as far as worldview so much as the attitudes of the actual people that we seem to have problems with.
>Trad RCC, EC, & other "Latin"-oriented groups I missed
Entirely focused on benefitting yourself and gaining for yourself salvation, at the expense of other considerations for others. Unable to understand why anyone wouldn't be an antinomian without this. Very accusatory of others based on false premises of being correct. Seemingly dependent on the reasonings of particular theologians, they don't realize that the choice of which generally-approved theologians to emphasize is left to decide by each person. And turning a blind eye to the vast amount of possible interpretations that results from this way of thinking, is paired with a "flexible" definition of what doctrinal unity is, sometimes exclusionary, other times incredibly superficial and relaxed, depending on the situation. Can't really agree what is binding and what isn't.
>EO & other Orthos
Similar situation with their set of theologians. However, this category doesn't seem to insist on that many strange doctrines, not overtly: this might have something to do with scholasticism. The minor branches have even more troubling Christology than the main branches of modern cathodox do, they're just not as obvious. They seem more interested in doing their own thing. Also have difficulties in agreeing internally what is binding and on what the final authority ought to be.
>mainstream RCC
Uses a potent brew of strange doctrines derived mainly from the "authorities" that have catered heavily to liberalism since the 1960's, and looking down from the highest pedestal at anyone who don't conform to the new morality. Not much different from mainstream protestants so far as being rigidly adherent to progressive nu-morality. Attempts to use the authority of fellow-traveler corrupt teachers as to "cover their bases," and being overly concerned with appearance and raw power. Very likely to be a protoplasm for the one world Religion. I could see it happening.
>Anglican and Episcopalian
Radically liberal, a physical continuance of whatever it was before the 1960's.
>Sedes
Basically, those who are too inflexible for modern RCC and became confused by Vatican II.
>No-labels churches (called "non-denominational" despite often being organized as one)
The remnants whatever notions of Christianity remain in a given area, post-1960's. Most of these churches are doctrinally adrift, and while they can be very conservative in the stereotypical boomer kind of way, are very likely to be subverted by talmudic judaizing influences at some level and to be slowly pulled into that dark void.
>Mainline protestants
By virtue of being known as mainline, these denominations are subverted from the very top, experiencing a continual effect of satanic "liberal" doctrine trickling down from the highest councils to the subservient churches in its grasp. Eventually this is how any large denomination will end up given enough time. The same can be said for all the "United" variants. Insufferably progressive and violently opposed to anyone that disagrees.
>Conservative protestants
These are the ones that are trying not to become the above. The biggest issue is that they seem to inherently follow the philosophy of the Biblical ((scholars)) when it comes to choosing a translation of the critical text and from this results in the average person who has studied all these things to treat it less seriously than it should be treated, because it could all be based on incomplete manuscripts. They have carried over some ideas from pre-reformation Catholicism that are hard to justify as anything other than tradition, including the confusion of somehow combining "the church" as they see it with government, a concept shared with all prots and which will be significant in the future. Bonus: The most likely to think Rabbis are expert at interpreting the Bible.
>Megachurches
Fun centers that have done a lot of work to blur the lines of what a church is. Not actually counted as a church, just worth mentioning as a separate case.
>Cults
These are not to be confused with any of the other categories here. Any of the pseudo-Christian groups that started appearing in the 1830's that plagiarize concepts from Scripture with little regard for anything but gaining and holding on to adherents. The leaders are interested in keeping their members in the dark and modifying scripture. The largest are the Mormons; there are others.