Thanks for the feedback.
Hungary: That is a better symbol. The slightly simpler version I used was pre-made, and thus easier, but I can do this one instead.
Ottomans: I would like to defend the current choice, which is from Rhye. It is the Tughra
http://en.wikipedia.org/wiki/Tughra and is a perfectly fine symbol for the Ottomans. The crescent is certainly more recognizable, but sort of boring too. I'm torn.
Venice: The flag should be the same as the button (without the border, which gets distorted in an ugly way). Unless I made a mistake...
Kiev/Moscow: Both the complex symbols for these two cities (Angel/St. George) look better in full color/large than small/two-color. I can do a better job on the Moscow one (I shrank it down too small and then made it slightly larger again, which is never a good idea). I'm not very motivated to switch the Kiev one when the current symbol is nice and simple, displays well as small size, and is perfectly fine for Kiev.
Arabia/Cordoba: Why do you want these two civs to have exactly the same symbol? That seems like a bad idea. I'm ok with giving one of them (probably the Arabs, since you hate the palm) this new symbol -- but again, I worry that it's a bit complex and won't look great shrunk down on unit flags/shields.
Bulgaria: I was thinking of the Madra Rider with the horse (which was pre-made, and thus easy). I'll see what I can do with any of the pictures you post. My other option was this seal
http://en.wikipedia.org/wiki/File:Coat_of_Arms_of_the_Bulgarian_Empire.PNG but it looked bad small in-game.