Removed: AIM, ICQ, YIM, MSN
added: Twitter, Skype, Pixeljoint

Are there others people feel strongly about adding?

I'd be really happy about adding "Deviantart" too

Regarding social networks (just from a modern standpoint):
Facebook might also make a lot of sense for many people, just considering the size.
Tumblr and Instagram might be important too

was mainly talking about the bricks, but great that you overthought and added it =)

There are 2 things you might want to check in your reference:

a) the color of the cast shadow. In your painting the cast shadow moves just towards a darker value. However light behaves differently and the shadow surely has another color.

b) the reds on the roof.
Your color scheme features mainly blue and orange and both are muted - realistically so to speak.
Your red is extremely highly saturated and I'd say it's "cartoony"
I am sure if you look for references of western towns and find red painted wood it's a lot less saturated and darker.
On the other hand I am not too fond that red fits in the overall color scheme. A bright orange might do a better job. Muted greenblue, a blueish gray or other colors might work better for this particular kind of environment.

some things I wanted to point out:

1) as already mentioned: work on a gray background.
If you want to have more of a painterly approach and work from a photo reference to get your colors and values, or try to get a photograph with fitting colors and weather conditions, it can help a lot.
Another possibility would be to get a stylized piece of art, if you are after a certain style and aren't sure how to stylize colors.
For the edit I pasted a neutral 50% gray and for mine I used a realistic base overcast sky color.

2) The big and important point:
work on the shading of the big forms. Texturing is nice and especially if we start out, we try to overemphasize minor detail (bricks & textures) over major detail, like the big forms of the house.
The architecture of the house can be simplified down in a few primitive cubes and pyramids which cutted tops.
It's really important to indicate plane changes (like in the roof) with value changes.
For my edit I brightened up the roof where the plane gets an angle closer to the horizontal, this emphasizes that those planes are coming towards the viewer and add a sense of space.

3) also consider cast shadows to establish depth relationships between forms. I added cast shadows beneth the roof, to really emphasize depth there and give a clue how massive the roos is.
Actually if it'd be a realistic painting with overcast sky the shadow would be a lot more subtle, but I wanted to communicate the idea what's happening.

4) the lantern (?) is a sphere. It's a bad idea to draw everything stictly from the front and to leave out any perspective. If the lantern is a sphere and no disk, the lines are "wrapping" around it. The angle strongly depends on the horizon and size, but generally I'd suggest that you look up how the horizon is used in a perpectivical projection. Even if it's for a game, using some of these perspectivical effect can communicate towards the viewer a much better understanding of form.

And maybe a 10% exercise of anatomy is all you need to make the best out of your 90% manga. Pain is to be expected, but fun is important. And I think the fun comes out of finding a work that fits your character, an enjoyment that has you forget some of the pain, likely to keep you on it more than once a month. And that this is positively visible in whatever work you do.

Fun is important, do what you like.
But good stylization or a well designed "style", requires a very good grasp on realism and what gets stylized, then just studying a style.

If you study a style without knowing why the style came together the way it is and what exactly got stylized, you maybe will produce ok art for that style.
But you can only transcend it and make it your own if you really understood how that style was "designed".

Manga in it's truest form is a stylization of reality, same applies to pixelart.
Manga can be drawn with just aligning symbols. Pixelart can be drawn by just putting down pixels.
a lot of people who ar ehobbyists handle it this way.

If you want to be professional or "a professional result", you have to know how to draw realism and the fundamentals of art.

To make it simple: there is absolutely no way to ensure you will get paid.
Even if you have a contract there is no way to be assured, that you will get paid.
Tons of companies went bankrupt, because contracts weren't fulfilled.

Even if you work for a company with reputation, or an individual with a "big name" will ensure you that you will get paid, because they already could be bankrupt or whatever.

The best way to ensure safety is risk minimization.

You can minimize risk by:

Research your Business Partner:
It's as simple as putting his name in google, on facebook and wherever, and looking through the results which show off. If there are multiple reports of fraud, it surely is risky. If there is one report or so, it's a possibility to show/ask your business partner about that (sometimes stuff pops up which might be very one-sided)

Half the Risk:
Your risk is time investment. your business partner's risk is "money investment".
For small business relationships 50% of the money in advance and 50% of the money afte rcompletion is the fairest way for both to deal with it.

Seperate the Work in Chunks:
If the work reaches a certain workload, some milestones need to get set. An example: a 10000$ job. Loosing 5000$ due to a fraud, is quite the risk for the employer, because it's a big chunk of money. But you can divide it in smaller portions too, which is the best compromise between safety and amount of transactions.
Make sure that you can back out anytime, if the emloyer doesn't take care of a partial payment though.

Set up a Written Agreement:
A contract basically is just a written agreement between both parties. Make sure to nail down the amount of payment, the time until the work/payment is done and the conditions for both parties to back out of the deal. Keep the written statements equal for both parties. Also make sure that the court of law is your court of law if your partner breaks the contract, and his court, if you break the contract.

If you don't think you can cover all eventualities yourself, go to a lawyer who can educate you on contracting and set up a basic contract with you. For certain jobs which are too big and risky you even want to set up the contract specifically for that job with a lawyer, but that's usually "company-level" only and doesn't apply in most cases to basic freelancing.
A contract can help in certain occassions, but is not the "magical potion" which will cure every problem.

Don't get baited by profit-share Profit share, or getting a certain percentage of a product if the product gets finalized might sound very attractive.
THe truth is that most game projects end as "vaporware" because game development is highly complex and new tasks show up as the development progresses.
So even if you did all the graphical work, but the dev has problems with a library, or with getting the game for sale in a shop, or if he just stops his own work, will lead to zero of the expected earnings for you.
And even if the product gets released you get what percentage/share of what exactly? Have you set all terms really clearly? Does your business partner have any understanding of taxes / shares etc.?
And even then he still could betray you and don't pay you anything - I won't expect that, but it happened.

I'd do profit share only with individuals you know that they will get "their shit done" (you know or worked with that person for a long time) and that they are in your physical reach. It's just to easy for someone to go black in the net.

Working with a friend you know since childhood and you did already some stuff together and you want to start a company: lowest possible risk, but still fairly risky
Working with a random person who just approached you via mail, has some company, no released products and you don#t know them, but they offer you a "profit share": wouldn't even consider touching something like this, because the possible risks outweigh the possible gains by too much.

I don't say: don't do it on any occassion. I just say, don't let that be the "bait" which will make you do the work. Always think about possible "failing-scenarios" really carefully.