Just like everyone else, I decide on whether or not I check out comics based on the art in the icon (or in otherwords I agree with A...)
The art of anything can make or break it for me, even if i find the story itself to be incredibly intriguing. It's a tad bit ridiculous how picky I am with the art style of something, crossing over into excessive. Ignoring how absolutely fickle I am with art, I like icons that, if it shows the mc, it shows their personality in some way? or conveys the tone of the story, if its long-form. Icons that are just headshots with a blank faced character are kinda bland IMO (this doesnt count SOLs or anything along those lines that are intentionally meant to be quick doodles or Other. this is mainly stories that are intended to be long form)
It's hard to say what really goes into a 'good' icon seeing as the space provided is too small to do anything that other General Design Rules would apply to (composition, values, etc.) frankly I just think as long as it Fits with the genre it should be fine, a silly doodle slice of life would be perfectly fine with a simplistic icon (as long as it matches the art style of the comic.) You can do little things here and there to make it stand out from others (such as coloring and etc) but beyond that, there is a Lot of limitations.
Speaking of limitations, I think also trying to deviate from the square resolution is a good way to catch some eyes? Kinda like the icon for A Better Place, which iirc immediately caught my eye as the series uses a circle instead of the square format.
Frankly, I just chose my icons based on panels that I really liked how they turned out like this one, for example, which is the icon for my main comic. Beyond just liking how the panel turned out, I think it also represents what the first few parts of the story are building up to lol...
