Leeneia, your items 1 and 4, relating to italics and all caps, it seems to me, are essentially the same. This is not a criticism, but my observation.

In each case, the physical representation of the letters and words forces an extra visual/mental conversion, so to speak, to what might be called standard expectation. A minimal step, to be sure, but a step. I find the conversion from italics to standard writing less of a problem than the conversion from all caps to standard. The use of italics for a word here or there, or for a book title, say, or a short quotation, is soon over and forgotten, but with larger blocks of italics or caps it becomes fatiguing.

Your item 2, dialect, probably comes to much the same thing. Of course "typed in dialect" might mean different things. If it refers to an attempt to phonetically indicate a dialectal pronunciation scheme (which I'm guessing is what you mean), it certainly can become obtrusive. Much like the use of italics and caps, a dialectal word here or there for "seasoning", so to speak, is absorbed without particular difficulty, but if there's an overload of phonetic representation it quickly becomes oppressive because of the constant semiconscious conversions that are forced.

Your number 3, large blocks of text, long paragraphs, may be related to the above. With long paragraphs a portion of one's attention has to be applied constantly, just keeping track of where one is in that big slug of stuff. Of course the rule is that a paragraph should represent one basic thought, but what constitutes a thought is a matter of judgment. An excessively long paragraph usually suggests to me that the writer hasn't really worked out what the real thought(s) is/are.

So all of your four points are related to some degree.

Dave Oesterreich