You can divide Kadikoy into 2 territories > Kadikoy and Bostanci (bordering Maltepe). Kinali ada should be connected to Bostanci.
You may also add an independent territory in Bostanci, called Selin's house

Another territory to be added could be Karakoy, bordering Eminonu, beyoglu, sisli and besiktas. Sisli has no border to bosphorus (sea border). So you can make sisli a little smaller.
You can also add names of Bosphorus, golden horn and marmara sea.
The two bridges on Bosphorus are very important for the chaotic traffic in Istanbul. You may think of the as being additional territories with some special bonus.
airports being able to attack any territory make little sense to me. you may want to start with neutral armies on both airports (eg 6 armies) and give +1 bonus added to the specific airport if conquered by a player (like in berlin map) and . If you want to implement this idea, you should take them both out of the colored regions. Another idea to give +1, +1, +2 bonus in total if someone owns both airports. (+1's to each airport, +2 extra bonus to anywhere the owner wants)
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