The thing you have to understand Mr. Rath is that the portrayal in many of these games your criticizing is pretty accurate, it's just not politically correct. Stereotypes exist for a reason, and the entire science of sociology is based around them, they are why things like advertising work and people make millions upon millions of dollar by understanding stereotypes and exploiting them. Not all stereotypes are nessicarly negative, but some are. You also have to understand that in practice a stereotype is a list of traits that you can check off which a given person or type of person is likely to fit. Most people won't hit every "mark" of a stereotype but will hit far more of those marks than they miss. Also people will generally conform to more than one stereotype simultaneously and can be targeted or identified from multiple directions. In general stereotyping and sociology is only an issue when it's negative or used to address big problems, then the politically correct brigade gets all upset. That doesn't prevent it from being accurate for most purposes though.
At any rate, you know some stuff about the "Cartel War" but really I think your missing a big part of the equasion. The USA is pretty much the point of the entire war. Due to drugs being illegal here huge prices can be commanded for them, despite those drugs being relatively cheap and easy to grow in other countries where it's not illegal, or there isn't adequete law enforcement to curtail it like there is in the US. The border wars are all about who pipes the drugs into the US for sale. We could argue the whole morality of drugs and whether they should be illegal, and how legalizing them would change things, but for the purposes of the arguement we're pretty much the victims here not just because of the violent spillover, but because of the drugs heading over the border that are coming in, in violation of our desires and presumably contributing to a lot of social problems.
The Cartel War being viewed from a mexican perspective is kind of pointless because on that end of things it all comes down to money, it's pretty understandable overall. It's a bunch of bad people fighting over exploiting the US. A big part of the problem is also that while Mexico does try and crack down on this due to their agreements with the US, there is a lot of anger and a feeling of entitlement to sell drugs in the US because it's something mexicans can obtain cheaply and feel should be valued, allowing them to have better lives, even if we disagree. Despite numerous "crackdowns" to say the actual efforts have been half hearted from within Mexico is an understatement, because other than good will with the US, Mexico has very little to actually gain from stopping drug trafficing. Indeed if the US was to ever loosen up it's laws, Mexico could loosen it's own, and woul be in a position to make a bundle through legitimate trade. From a Mexican perspective, attacking drug lords, as bad as they are, is pretty much shooting themselves in the foot for the benefit for a foreign power that doesn't want to accept their trade.
The idea of Americans going in and resolving this is common because in the final equasion we're pretty much the "good guys" as far as such a thing goes, since at the end of the day our entire motivation is simply to decide what happens in our back yard. Hence the "power fantasy" of kicking so much butt that the problem ends (or at least is reduced). For a lot of people in the US it's kind of maddening that we can't just go in and nail the guys involved when they are over a border we currently respect.
There is some truth that our free access to firearms (well relatively) especially in the south and in some of the border states means that a lot of the weapons used in the cartel wars come from us. Not to mention that guns 4 dope is a pretty straightforward trade for those who can get firearms in bulk.
When it comes to the issue of mexican civilians, you have to understand that when your dealing with video games, your dealing with the portrayal of a very specific situation intended to be exciting. To be fair in the middle of a cartel war zone where some gun toting spectre of vengeance is going to run into many civilians, everyone there being a narco isn't surprising because anyone who wasn't would have gotten the hell out of dodge by that point. Also understand that these games are also single focus, they don't even claim to show all of mexico (which has some very nice areas, and some incredible tourist traps) the stereotypes used are indicative of the kinds of people you'd expect to be around in an envirment ready to break out into a massive gunfight any second.
Your also correct that there is creative liscence taken, the cartels have never bombed a DEA building. They have killed cops and such (interfering with their business US side) but a massive display like that would invite exactly the kind of response these video games propose. The US might very well finally lay down the law with Mexico and say "you will tolerate the DEA going in and kicking butt, or our military will invade you given the extent of this attack" in a way you generally don't see happening. BUT that is exactly why the real cartels won't attack on that scale, they want to skirt around making themselves that much of a problem. The idea of some unusually crazy cartel leader who doesn't "get that" going too far makes for a great set up for some action fantasy though.
When it comes to human trafficking, it works both ways. When it comes to sexual slavery girls who are differant/exotic from the norm in a given area are always popular. Thus human traffickers will sell say Asian or Latino girls in the US, and white girls in Asian and Latin markets, it works both ways, and those really into it are unlikely to trade in only one direction. Globally speaking whites are in high demand internationally because we are perhaps the smallest and most exotic percentage of humanity, the Chinese alone counting for like 1/3rd of the human population, with India counting for almost another third and set to overtake the Chinese. According to many studies (census accuracy is difficult) Africa and South/Central America's now-indigious populations outnumber the white countries by a substantial amount also. Wealth is also a factor, getting a white girl is a little more difficult (though not terrible so with the state of some european and slavic countries) than other ethnicities.
Finally, you mention a Mexican protaganist. Don't get me wrong, I am not going to say that Mexicans can't be heroic in many situations, but when it comes to the cartel war I don't think the perspective really makes for much of a sympathetic game. The best you could hope for would be a game that seeks to put the blame on the US, basically from the perspective that if we just backed down and bought all the drugs legally these cartels couldn't operate. After all that is the central tension that drives the whole thing. That might earn some points in Mexico and other drug producing countries, but not so much in countries that don't want drugs, or have very strong attitudes about their right to decide what's imported into their country in general. In the final equasion that is the only real "ultimate perspective" that is going to work in the big picture, and few of those who play video games would go for that.... though admittedly many left wingers who themselves want to legalize drugs might agree with it on that level alone.