For Aguascalientes it seemed important to me to somehow express the idea of "warm water" - but I didn't like the drawing of a water fountain that is on the current flag. I did, however, find the colors of the shield usable. It was only after uploading the second proposal that I realized that the color combination on the first one is not half as good, and that the second should have replaced the first. Although it seemed natural at first to put the blues together in the center, representing the water, I realized that on the original flag "warm water" is also represented by grey, and light blue is a background color that could symbolize air. Anyway, the second proposal seems much more balanced to my eyes.
The current flag of Baja California, while being an SoB, has plenty of colors and symbols to choose from. The one thing that is striking about it is the man standing in the middle with his arms spread wide. I took this as a hint as to what geometry was required.
For Baja California Sur I took just what's on the center of the shield - a white shell on yellow and red - and made that into a flag. I did not think that the blue border adds value to this flag, so it had to go. For the shell I manually traced the shell on the current flag and used the outline without any extra lines.
In a second version I did add a border and fishes.
The current flag of Campeche is a very complicated and visually muddled design. Some of the most obvious remedies have already been proposed, so I looked if I could rearrange the colors blue en red in another way, giving them each exactly the same amount of space. The flag I ended up with accidentally spells a "C" in white, which can be seen as an added bonus.
I found the flag of Chiapas hard to work with, with a complicated design that doesn't lend itself well to simplification. So, I decided the best way forward was to take three of the colors from the flag and arrange them in horizontal bands.
The central thing on the shield of Chihuahua is undoubtedly the brownish red checkered pattern. Others have shown that it's rather difficult to create something beautiful with it, but I think I succeeded at that. As an exception I loaded the flag with a shield, to keep the central gem - a flower - safely away from the agressively checkered pattern. I found the support color blue very helpful to achieve this.
The shield on the current flag of Coahuila holds three pictures - none of which are terribly specific for this region. The first two (two wolves around a tree, and a red lion mounting one of the pillars of Hercules) tell us something about the Spanish heraldic tradition, but both are also found in other state shields, and neither is relevant to Coahuila. The third picture (the sun, trees and a river) could have served as a basis, but having done similar landscape based designs I was not thrilled to do another one.
The only thing left was the overall arrangement in three compartments, and a very wide range of colors to choose from.
The central symbol on the current flag of Colima is an arm with the hand twisted the wrong way. I didn't find this an attractive symbol to work with. The red border of the shield, however, did please me, so I kept it. In it I placed a blue triangle, symbolizing the vulcano that is depicted under the shield on the current flag.
The shield depicted on the current flag of Guanajuato is a thing of beauty, with its well chosen color palette and with its swirly forms - but it's quite unsuitable for a flag, as the picture is tiny on the big white bedsheet. I put the host that the holy figure is holding in his right hand in the center of the picture, wrapped in and protected by red en blue shapes.
For the first proposal I used the pastel colors taken from the current flag; for the second I concentrated the colors ("eliminated white") to get a more vibrant flag.
The shield depicted on the current flag of Guerrero holds a man holding a shield. It was this inner shield's pattern that I sought to understand and copy. The first version is as close to the shield's design as I can get, and the other two are variations (which helped me perfecting the first).
The first two designs were based on the misunderstanding that the word "hidalgo" means "knight". It doesn't. But as I was unaware of that, I designed a knight's helmet (varying on someone else's example).
After I became aware that the meaning of the word "hidalgo" is in fact "nobleman", I found a Spanish hidalgo crown on Wikipedia, designed by Rolando Yñigo-Genio, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31528985 . I used that to make the third and fourth proposal, and quickly took my first two proposals down from the "Hidalgo" page.
On the new flag of México City is the glyph of Tenochtitlan, the starting point of México City. The background color and the color of the border are from the shield on the current flag. The glyph was found on Wikipedia, and has a PD licence. It represents (at least) a flowering cactus, as far as I can see - a beautiful and ancient symbol for México City.
It seems obvious to me that the flag of Nuevo León ("New Lion") should contain a Lion. In the first design I put the lion on a background of orange trees, as seen on the shield; in the second I have a lion that is red, like the lion of the Spanish city Léon, but I maintained the oranges as a discerning symbol.
This flag design is completely inspired by the current flag. On red parchment, which symbolizes the battles for freedom of the Oaxacan people, is an elliptical shield that holds on the left nopal (a cactus), an old Oaxacan symbol of wealth, and on the right seven stars, representing the regions of the state.
The background is inspired by the design of Ricardo Vazoli. As he describes it: "A curve from North to East [...] defines the Gulf of Mexico." My true (vera) cross is a Latin cross, i.e. it has three equal arms and one longer one - like the one on the seal. The same colors are used as on the seal.