I'll say B, mainly because for me, keeping it simple has worked out fairly well, especially on the webcomic list(It's literally just the title of the comic on a white BG). I'm sure a great icon is important in some way, but with no metrics to track its effectiveness(I'm a numbers guy), I just feel like it pays to keep it simple when everyone else is trying to impress.
When I mentioned this before, my concern was the colours are very light and the contrast low. The lineart is also not black, so if the size is smaller I personally might have struggled with seeing anything other than 3 figures.
The good thing about it is it gives you the right idea about the art in the series and it effectively communicates t has 3 main characters.
You can improve it by:
Anyways, this is only a well-wishing advice, feel free not to take it if you fit it doesn't fit you or your series. 
When I made the icon for my comic (pictured below) I was mainly just thinking that I wanted something really bright, like you said. I've noticed that, at least for myself personally, someone could have an amazingly well-drawn icon in b&w or dark colors, but I won't find it eye-catching, yet someone could have a mediocre drawing in primary colors and I always see it. And while I'm no expert, I think my icon's pretty good, because whenever my comic is updated it gets a lot of clicks from people seeing it in the 'fresh' section. Also, I think you're so right about the background being filled with a bright color instead of just being white. Great post XD
thank you for the advice! i agree w your point about the empty space - maybe i should go back and change the angle of the arm a bit ?
my new icon definitely matches the tone of the comic much, much better
My series6 debuted recently, but the style changed to fit the story. I find it difficult to keep my icon simple without making it boring.
The first is the one I uploaded, but I'm not sure if the second is slightly better?
2
I think the second one is better. I can see the style more clearly and the shapes you've used look dynamic and interesting. It's simple and effective. Nice!
I think people sometimes forget that the name of their comic is displayed directly beneath the icon itself and try to squeeze the title in there out of worry. Don't do it people! We can see the name just fine, save your precious icon space.
To me, the right icon is a definite improvement. Just by omitting the title, it gives you enough space to include her neck and shoulder, which lets us know so much more of the character. There's more focus on the characters expression now that it's centered and no longer competing with the title, and the motion created by the hair is increased. Even as a tiny icon, it looks good.
I just switched my series icon from a half body shot to a more dynamic facial shot of the main character (taken straight out of the comic because I happened to like the panel) and it does seem like a more dynamic avatar could be pulling more views as I update since I've gotten new subs with both updates I've done with the new icon.
And then there ofcourse is the fact of just finding the icon look that will attract the kind of people who are likely to be interested in your comic. I don't think everyone will be interested in the same kind of an icon, but when you get sub-ratio compared to views going up then something is going into right direction at least.
Right after reading this topic I changed the Icon of my series1 to this.
The most dynamic icon I could find.
i'll wait on next update to see the difference.
But I already got a bunch of subscribers which means it works... i think.
Hope it doesn't spoil too much for the readers and encourage them to check the series out.
Time will tell. Not afraid to change again If needed. 
I'm very curious to know whether or not folks would yes-click based on my current icons. I feel like they're good, but I also know other peoples' insight might be helpful! They're both pulled straight from the comics rather than creating a unique image not seen in the comics.
I would click the second one because it's really interesting, mysterious with the monster lurking in the background, and you immediately see it's fantasy and more on the adventure/battling side of it.
The first......not so much. while it definitely needs skill to make what seems like a 3D-model, the potential reader has literally NO idea what this is about. Maybe just a punk girl in high school. Maybe a gay bar where she's the bar tender. Or it's sci-fi but we don't know because the background is literally blank which is quite odd if you already have such a very detailed/textured character (since it is sci-fi, a space background would provide a bit of context). Like this, it looks a lot like "I was playing Sims4 and cut out the characters but kinda don't know what to do with them."
I think a smaller scale that only shows the head might be more interesting as well, also if you shift it more to one side, it probably looks a bit more dynamic.
I hope that's not too negative as a critique but uh-huh yeah.
It's funny that I should see this thread today because I've just spent the past few days figuring out how to make my icon appealing and eye-catching. I hope I can offer some insight to my thought process and receive some suggestions.
This is my first take on my icon. I liked it as an individual piece, but I wasn't sure if it stood enough, and I didn't think it conveyed the tone of my story. It looks more light-hearted and fantastical rather than the slightly more action-packed, richer, and psychological tone I was going for. From here, I painted over the icon into this:
Although I liked the lighter one better, I thought this one popped more with the contrasting colors, and portrayed the tone better with the harsh colors and darkened, averted eyes.
So I made some in-betweens of these two icons and put them to the test. I screenshotted a page of popular/trending comics and photoshopped my icons over existing ones.
I avoided putting any of mine in the middle because I think that's where the eye naturally goes. After looking at this, I thought that the red background made icon #2 too busy and the face was too dark and unreadable from a glance, and that I quite liked how the faded yellow of #1 looked amongst the others. For now, I think I prefer either the uppermost or lowermost icon in this test picture. Of course, all of this would change depending on which stories show up around yours. Maybe I went a little far by doing this, but what minimal training in graphic design I had was itching at me.
Some feedback would be nice, although I may redesign the icon entirely again to better match my story (which is unpublished and will probably stay that way for a few months at least as I work on it).
The icon is what draws your attention--if a person has put a lot of thought and effort into their icon, then it's a good sign they put a lot of thought and effort into other areas in their comic. However, this isn't a 100% guarantee of the comic being of good quality. So, I'm somewhere between A and B on this one.
Icons are tricky, but a lot of the readers of my comic3 say they thought the icon was cool and clicked on it. I'm not entirely sure what my team and I did right by it but here you have it:
The thought process in designing our icon:
- We featured the main character, and the duality of her roles.
- We wanted to show a little bit of the world
- We wanted it to show off the art style of our comic
- We decided it was kind of redundant to put the title in the thumbnail image because it's so small and the title's already below the comic in the line up anyway.
Actually: Okay here's a pet peeve of mine. I'm not a fan when icons have a crap load of words in them, or really "whimsical" font types for the logo they throw in. The size of the icon is so small, why waste that space on text when all the important information is already presented for you else where? Also comic icons where you can see the text bubbles. Every now and then for my comic I'll make an episode icon where the text is seen, and it's like...eye twitchingly frustrating for me. No one can read it. No one can see it. While it might have an interesting point or tagline being said, it doesn't matter if it's there if no one can read it.
^^^^^^^ ALSO THIS x10000000000
OK, I feel like I am dreadful at icons, cover pages, banners, etc.
This is my current one and well I don't think people find it very appealing but I don't really know what to do to change that.
This was my original icon but I didn't like it because the style didn't 100% match the art style in the comic.
In the photoshopped screenshot, I noticed the on in the middle right first. (Your first icon in your post.) It caught my eye.
I liked the bottom one more than the top (Although the high contrast definitely caught my attention) and I didn't notice the middle left was even there for a few moments (which is strange - it's rather striking as well.)
The middle right one feels more approachable, fun/mischievous (a bit of a smirk on your character's face), and like it could involve something magical or mystical?
The top one seems a more dramatic, intense, and (with the stern look your character is giving and the red) possibly even violent?
I think the bottom one is a good blend of the two - approachable and dramatic. Mischievous and intense.
Sometimes simplicity is the most striking. That's why I used stencils in the icon for my comic1.
I agree. Simplicity, in my opinion, adds a flair of mystery to the icon, and sparks curiosity in the viewer. For example, I've seen quite a few different icons with simple objects or images that leaves a lot to the imagination. This leads readers to think "Huh, based on this image, I wonder what this comic could possibly be about?", which in turn leads them to click on the icon.
It's also effective if you have colors that catches the eye and seems appealing. That's why I decided to use bright hues in my icon so that it stands out the most.
