I have a few, although I speak more as a general writer than as a comic enjoyer:
First, the prologue that serves only to give a deluge of information to the reader. This is a very common gripe as is evident from this thread, but my issues with it aren't solely because it's "lazy". I think anything if done in an interesting way can be good. My issue with such introductions however is that often times its purpose seems redundant, as you'll likely have to re-introduce/explain certain bits of lore later down the line as people may not remember, and at that point it makes you wonder why you needed that prologue in the first place. Information should be given when relevant, and it should for the most part be given as naturally as possible.
Second, and this is more of a general story-telling thing, but the lack of notable flaws in characters. At best you get things like being clumsy, clueless, or being physically weak, but to me that's not much to get interested in. I enjoy emotional conflict as much as I do physical conflict, so it's admittedly disappointing to see very little of anything of the former that goes beyond surface-level issues. I like to see genuine, crippling flaws in a character's personality that makes them cause problems, make enemies, and is something that they try to actively work towards fixing. your character doesn't have to be a jerk or an anti-hero for this of course, you can have a more "heroic" protagonist or side-character and still give them some kind of imperfection in their soul.
Lastly, there is something I prefer to call "Lore-Bloat". this is more common in newer creators but it's when a creator has so many ideas that they wish to utilize while having a comic that can only carry so much, but they decide to cram everything in rather than just save some of that creativity for a future project. lore is amazing and can bring great depth to your story world but there comes a point where it becomes too much. bloat can cause the story to become convoluted and confusing, making it hard to keep up with the work, or alternatively there's a great portion of content that has little to no connection to current events so it feels more like useless trivia.