Thoughts before I send it away to print?
Here are my honest thoughts. I'm not a fan of the mismatch of art-styles. It's what I've been saying about the state of this hobby in the last handful of years, too many of these projects have been revealed with a mash-up photochopped artwork, based on the owner wanting to put every favourite character of theirs onto their cabinet. What this does is make the overall look seem "cheap", and creates a non-themed artstyle that just ends up looking confusing. That being said, you stated that's your preference so I'll just leave it at that...
You mentioned it's a Japanese themed cabinet, but it's not really that since the subject matter is actually focusing on the characters. But what you do have as Japanese is a very stereotypical trope of Japanese culture: Rising sun graphics, The Great Wave off Kanagawa art... this is like what the western world regards as being "Japan themed".
Marquee: Not a fan of the characters sticking out of the letters. First, it makes it very difficult to read, and it's forced you to segment your name. Secondly, some of the characters aren't properly lined up to the outlines of the letters, so it looks a bit messy. Look at how everyone except Rapheal overlaps the bottom black outline, while Rapheal keeps within the outline. And having them stick out like that just looks odd to me. If I were you I would have made the letters much bigger, and encompass the entire characters within the letters and not have them stick out like that. That way your letters will read better, you'll utilize more space on the marquee and you can increase the amount of character graphics you're showing. Remember, bartop marquees are small, so you'll want to maximize the space as much as possible for readability. Right now you have a lot of empty negative space between and around the letters, which is just wasted space.
The faded out background is for sure not going to look nice once it's lit-up, it also looks like you scaled the images a bit too much from their original resolution because I'm seen some blurring artifacts. I don't even know what you're doing with the sun rays here. The top edge has many rays, versus the bottom edge has half? And the angle of the lines are not consistent! I would just get rid of them. But if you're stuck on having them there, then I would suggest having the lines come from the center of the image, that way the lines will look like they're emanating from the middle rather than passing through at different angles whether on top or bottom.
CP: Spiderman's crotch joystick, definitely a cardinal sin when putting together a CP graphic layout. I don't know if you have kids playing on this, but I'm pretty sure even immature adults will crack a joke about grabbing onto Spidey's knob.
I would also lose the sun rays here. Actually, I would lose the sun rays on everything except the sides. You don't really need to splatter your cabinet with the same graphic elements on each side. You could simplify the CP and Marquee elements and it can still go with the rest of the graphics, especially if you're sticking to the same colour scheme. Sometimes less is more. I think this is a good place to simplify.
Sides: Just so much going on. You've got vertical blue and white lines on the front edge, then diagonal sun rays in the rest. It's like those blue lines are slapped on there to fill-in space. I would get rid of that and just let the background graphics show through.
I'm not sure why there is a glow on the Wave graphics.You're already getting a good contrast between the background and the wave, so that extra glow makes it look very amateur. And speaking of that area of the sideart, on one side you've got the rising sun showing completely, with rays emanating from the Sun. But on the other side you've got the sun rays emanating from the wave? It's a little strange. It would have been better if you tried to have the rays continue their angle from the rising sun side, so there is continuity between the two sides.
Also, what's throwing me off is that you're using the old Japanese Rising Sun flag graphics, but your background is set at night? The Rising Sun is supposed to signify the brightness and warmth of the "Land of the Rising Sun". Every piece of Japanese art that uses the Rising Sun is set in the daytime, which makes sense since the sun being out means --daytime--. I would just have the Rising Sun graphics keep it's Red and White colors rather than outlining and showing the dark blue between each ray.
Anyway, there's more that I have thoughts on, but these are the major points I feel are a bit strange to me. I apologize if you're offended by this, but these are my honest thoughts, which you've asked for.