That said, I personally look at it and think it's fine - like, my opinion when I look at it is "Yea, there's nothing wrong with that". In fact, until about 5 minutes ago when more than 1 person said it wasn't good, I was rather proud of that banner. It makes me wonder where the disconnect is, where I look at it and think "Yea that looks good" and then other ppl look at it and go "Actually, that sucks".
As a fellow Dev I can relate to this. I can't count the number of things I've released that thought looked amazing, only to find out they were indeed shit. So, we need to never stop improving.
And when you say things like "Comp is bad" I literally don't understand what that means. And the colors to me? They look fine. Again I'm not arguing what you're saying, im just saying to me, I don't see what you see, and I wonder why?
Here's what I can see:
* The image has no focal point. In art you always want to have a primary focal point, otherwise the image looks scattered. When it comes to colors, detail, content, and contrast there's no real focal point in the image. This can't be understated, a single focal point is extremely important for image composition. You can have a secondary focal point, but it should be subservient to the primary one.
* The posing for the woman on the left looks off. Her head looks bent very far.
* Where is my head? My head looks like it's coming out of my shoulder. That's the main character's left arm on the right side of the screen.
* Beach sand looks flat on the parts where the feet are touching it. I understand it's a paralex texture, you can hide the feet touching it with cropping, shadow, or occlusion.
* Expressions look boring. all perfectly symmetrical. all essentially the same. Every single character smiling with open upper teeth, perfectly symmetrical, flat eyebrows.
* Colors. Seems like mist opportunity for sunset colors, and harder lighting. Usually people have campfire's on the beach after it's starting to get dark. A camp fire during the day feels boring to me.
* The character's eyes look like they're looking in slightly different places.
* I can't tell what the character is doing with the alcohol. If he's about to open it, his other hand could be on it. If he's about to toss it to another character then that character could be getting ready to catch it and the MC's arm could be about to toss it.
* Why does that other dude have a girl in the picture? Feels like NTR to me. This may limit your audience.
* The fire looks very flat. I'm not sure if there's a better way to do that.
* Colors don't evoke any emotions. Not particularly saturated, but not particularly grey/depressing. There's no single color to tie the image together and make it feel cohesive. For example, making the entire image feel warm and yellow.
* Not enough interesting occurring. By interesting, think unexpected, dangerous, crazy, or intense. From the picture it looks like the game is about friendship but friendship can be more interesting. This may be a personal preference, but I want a bigger hook: A dead body, a monster, a character that looks goofy/deranged, conflicting character emotions, something.
Btw, If my Teen Titans game I'm publishing v0.1.0 today/tomorrow, never get's much attention I'll probably ask others for visual feedback as well.