We noticed that most of the negative feedback is based on low performance in some situations. Indeed, performance drops when player unlocks really many cities and spawns hundreds of planes (it's noticeable only in Free Mode - it's almost impossible to spawn that many planes in other modes). We are working on fixing this problem, in particular we are optimizing algorithm of calculating plane's position on the map and generating passengers in airports.
The work is still not done, but you can already see the first results - hundreds of planes and stable 60 frames per second! At the same time, we are refactoring code that launches different game modes, loads and saves the game. In the future, it will allow us to work on the game more effectively and will fix dozens of bugs.
How about joining our Discord server? Different game tactics are discussed there, and sometimes you can directly chat with the developers :)
Here's the link: http://discord.gg/invite/9eHyYap
Our page on Twitter: https://twitter.com/kishmishstudio