He's looking good.

The only thing that stands out to me is his left leg. It seems to get thinner as he steps forward. It also looks smaller than his right leg since you can see his right leg behind his left leg. I think part of it is when his left leg is fully forward, his leg goes all the way up to torso into his shirt. Instead of ending at his pelvis like his right leg does.

But the shoulder twist looks great. As well as the lighting.

I'd wonder what his eyes would do if you changed them to a color. They seem a little beady as is. But I don't know that it's that big of a deal because it reads well and that's the important part.

His hat looks great. I really struggled with the hat on my sea captain.

If it's menu that is mid play, I would just have the current background with a solid color set to 50% or so transparency. If it's ab entirely new scene or layout I'd say more of those pipes that the foreground menus are made out of but with far far less contrast. But even a solid color that isn't black Stark black would be better. Maybe some simple texture patterns could work too.

That's a fair point. Here is how I'm handling god rays in my game.

It's looking really good.

The main hull looks great. But because it's so well textured it makes the fin in back stand out a little more to me. Whether it should be overall more midtone? Or add some shadow to the bottom of each plank to give it depth? Not sure exactly. It just seems like it's a little brighter than the main hull. But the wood texturing and rivets look great to me. 

I like the shading you have on the 3 windows at the side, but I think you could take it a step further to show the curvature of the windows with the highlights. I did a rough attempt that hopefully gets the idea across.



As for the animation, I know it's not strictly pixel art, but I like the water affect on the plants in the animation you have. Looks really natural. I'm making an underwater game myself, and it's tempting to throw filters on things and it's hard to balance what looks natural with the pixel art and what seems like a cheap affect to give movement to still pixel art.

The godrays are more up to personal preference, but I had good luck using a solid transparent color and having them overlap. They don't look as "real", but they seem to blend better with the pixel art. You might also move them behind the sub. When they are in front and the lighting on the sub doesn't account for the depth and "form" of the sub it's easier to tell it's just a layer in front of the sub. It may also make the sub contrast more with the background? Then again it may compete more with the background.

Looks great overall though.

Side note: the menu options look nice. I always struggle with UI stuff and it looks really natural here.

In the sketch I'm referencing she has a fan which works really well, but when you mentioned it I thought it would be funny if she was covering her eyes even more (the idea of the character is she works outside on a picturesque beach but generally hates being outside). I may have to mess with the placement of her hand so it doesn't get in the way of her eyes too much. I tried to add sweat because that would further the bit about her hating to be outside in the sun but all the sweat was either too big or looked like pixel noise. I'll have to keep working on it.

And lowering her eyes like you suggested works really well too. Thanks for the suggestions. I'll have to put a little bit more time in refining the ideas but they are subtle things that make it a bit more humorous.