Of those elements?
Hentai Anime:
{1. Story}
2. Genre
3. Character Design
4. Sex Scene Duration and Quantity
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5. Angles and Positions Used in the Sex Scenes
6. Type of Characters
7. Animation / Fluidity of Movements
8. Voices
9. Censorship Level
Comments: #1-4 are the ones that determine whether or not I will delete a hentai once I download it. #1 is in brackets because, when it comes to hentai anime,
a good story is as elusive as a unicorn. Pretty fucking rare. But they do exist, and when they come along, ho-o-ly shit. O_O

I know that for you the noisiness of the guys grunting or saying stupid shit is a big deal but for me that ranks pretty low on the list, even if I agree that they're a nuisance. I just ignore 'em! Same for if the female seiyuu has a really annoying voice.
Hentai Doujinshi or Manga or Magazine Publication:
1. Story!!!
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2. Character Design
3. Genre
4. Type of Characters
5. Legibility
6. Sex Scene Duration and Quantity
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7. Frame Transitions
8. Angles and Positions Used in the Sex Scenes
9. Censorship Level
In place of "Voices," I'll say "legibility". Is the dialogue typed or handwritten? Is it boringly repetitive or so unique I'm having to bust out the dictionary too much? Legibility
has made or broken (as in the saying "make or break") quite a number of stories in my time. It's the ones with great art and great narratives but really shitty handwritten speech bubbles that stand out in my mind, obviously, because nobody pays any attention to a shitty story that happens to have clear type-written characters. lol Clear-type written speech bubbles are (
thankfully!) the rule, not the exception.
In place of "animation / fluidity of movemens," I'll say "frame transitions." How well does the artist make use of comic book-style frames to tell his or his partner's story? Does he manage to pull off a sense of motion by drawing in solidly a pair of breasts swung in one direction and then outlines those same breasts in a different direction either a) in a different frame very close by or b) in the same frame but with lighter penciling in? Does the story flow naturally without reading any of the dialogue (i.e.
ask your local weeaboo if he can follow what's going on!) or does the artist jump from frame to frame so sporadically (and often relying on what's been said in speech bubbles) that the casual reader feels lost and the masturbator soon loses his will to jerk off because he can't predict where in the sex act he's going to be when he turns the next page?
Anyway, I've ranked the list this way this time because:
a)
story is key! At least for me it is. And good god do we have a lot of great stories in printed hentai! So if the story is shitty, I pretty much waste no more time on it. Even if #2-#9 are all fantastic, tough shit -- I flip through the pages digitally at like one image file per 0.5 seconds to say that I've technically "read it" and to make sure I'm not overlooking any possible gems (especially if it's an author's compilation tankoubon) and then I pretty much send it off to my bronze medalist folder.
b) #2-#6 (in addition to #1 above them) correspond to #1-#4 for the Hentai Anime list above: in that
these are the factors which for me really make or break a hentai. The other factors matter, just not as much.
c) It really should be emphasized that
censorship in printed hentai is laughably absent or near-absent. The tiny white or tiny black strips that they use are so thin that you can still see most of the woman's clitoris when these strips are superimposed over her vagina. Sometimes they only censor her vagina with as little as
one thin censor bar! It may as well not even be there. I think I've been reading hentai for so many years that my brain doesn't even see it -- well, I
know this is the case, I'm just hypothesizing as to what the cause may be.

I can't tell you the number of times somebody has complained about censorship in a story and I've had to double-check because I couldn't even remember there being any censorship at all.
d) Legibility can be a very serious deal. I already talked about that above, so here's a sample picture from a story that had very erotic art, an erotic plot, and yet I just couldn't fucking stand it because the author's scrawled handwriting was
SO ILLEGIBLE that even though I knew every single word he was saying I was spending minutes plural just to decode a page at a time. Really fucking interrupts you when you're trying to masturbate and enjoy a good story at the same time. :\
Note that I was not viewing the image in full-res but rather at an image height of approximately 1000 pixels (so 5/8 or 62.5% resolution), so be sure to view it at those same specs before you tell me "oh dude it's so legible." Because yeah, I agree that it's legible when you have it zoomed in to its standard definition -- but unfortunately that's too tall for a 1280 x 1024 monitor display resolution (
MINE!) and so unless I want to zoom in and use the mouse to wheel up and down every single time (no thanks -.-) and to only see half of the woman's body on full page displays (again, no thanks -.-) then have some sympathy please and understand why I'm viewing them at ~1000 pixel height.
Besides,
no hentai circle with even an ounce of professionalism should be scribbling in their text. Is it that fucking hard to scan your stuff into a computer and type in the text?