A while ago, I conducted a survey on this very forum about Independent Game Development, and your stories (in a sense). The responses have since been integrated into my Senior Research Paper.
So the formatting can be kept, the paper will be uploaded as a PDF.
PDF download/online viewer: http://www.mediafire.com/view/?451926d9ru6m8y0
If you see any grammatical errors, spelling errors, or anything sounds weird, I would GREATLY appreciate the heads up 
/me Puts on the English tutor hat
(Nota Bene: I’m not trying to be rude with any of these comments, they are the same information I would give a paying pupil. However, it’s late and I’m pressed for time so these instructions are terse. Take them with a grain of salt, I know how hard it is to receive criticism on a paper you’ve already put a ton of work into.)
The last sentence of your first paragraph is redundant. This section should be reworked.
First sentence second paragraph “large majority” does not apply and makes no sense in this context. Perhaps “large number” or “the majority of extant game engines” is what you mean here.
This sentence:
The reason why a game engine is so important to game developers, is because it is what handles the majority of the game.
is poorly worded, You have a lot of superfluous verbiage here. Try “The reason a game engine is so important is it handles the majority of the game.”
This sentence:
A game engine dictates the visuals (to a certain extent), how the physics interact, navigation, the computer-controlled characters artificial intelligence (to an extent), and so on.
Makes a weak argument. Regardless if someone agrees with these tenants or not, the fact that you have to qualify all of them should raise a red flag. I’d suggest just focusing on other things you don’t have to qualify such as: “The game engine abstracts things like pathfinding, physics interactions, and creates a framework for the coding of the business logic of the game. This allows the developer to focus on the portion of the programming that makes a game unique and fun rather than the nuts-and-bolts under the hood items that tend to be handled similarly across most games.” Obviously don’t use this verbatim, but it makes a much stronger argument and clearer point.
This sentence:
“Each has zealots (or someone who avidly supports that game engine) …” First, don’t define zealots, you should expect your audience to be able to read high school level English. Second, it should be the start of a new paragraph as you are changing subjects entirely here and the following sentences are in support of this point.
This sentence: “Developers have diverse specialties, including game design, programming, and art.” (Liming). Doesn’t seem to belong with the paragraph it comes at the end of. I actually wonder if it was a mistaken cut and paste.
This sentence: However, in independent studios, there is often only one programmer, who handles coding everything, such basic game mechanics, such as moving, to more specific game elements, like sanity, to menus and graphical user interfaces. Sanity? I’m not sure what you actually meant here. I’d suggest just getting rid of that phrase entirely.
This sentence: Another major job in the game development industry, is 3D Modeling. Again should be the start of a new paragraph. It is completely unrelated to the paragraph it comes at the end of and is supported by the following several sentences. You actually do this throughout the paper. I think your intent is to set up the next paragraph, but the effect it creates is to leave the last sentence dangling, unrelated to anything that came before it in the paragraph. Changing it or leaving it as is will be your own choice of course, but I would doubt many professional writers or English teachers would consider this good style. Of course, now I’m wondering if your instructor taught you to do things this way… That makes me shudder a bit.
This sentence: The average independent game developer will never make $30 million combining all of their games together, let alone from one single game, in fact, one out of ten independent developers even sold more than 10,000 copies of a single game.
Is run on and should be broke into two.
The next one: Thus, this limit of profits equals a limit on the hardware the developer can get, a limit on hiring people with more knowledge on a subject than them, such as outsourcing 3D modeling to another person, or outsourcing writing scripts to another person. Is very awkward and should be reworked.
This sentence: A lack of access to funds severely limits what an independent game developer can do. Should come earlier in your paragraph, as it is a broader statement than the more specific ones that currently come before it.
Don’t take a passive voice as in this sentence: If the game fails, that million dollars becomes effectively gone, and the developer’s reputation gets scarred as well. Try it more like this: “If the game fails, those millions of dollars are lost, scarring the developers reputation in the process.” The key difference here is the money is not “effectively gone” it is just plain gone.
This sentence: As is clearly visible, Independent Game Development has limiting factors, like forcing all jobs onto a small team, that makes independent game development much harder to create games, while providing more innovation than triple-A development teams.
Is also run on. You should consider reworking it or breaking it into two sentences.
Also run on:
An independent game developer first has to choose from a large multitude of engines available to them, and then learn how to complete all the jobs required by game development, and then does not have nearly as much funding as triple-A studios, but they can ultimately create more interesting games since their creative freedom is not limited.
You seem to be loosing focus here as you sprint to the end of the paper. Keep your sentences tight and focused.
Best of luck on the paper, and in your future as a game developer!
Cheers!