I enjoy the game a lot, and have been playing it on and off for a while now. However, there are some things I find lacking:
1) Bux
It is always a struggle for me to collect enough bux to build and aircraft. I find more often than not, I have to watch a good fifteen ads just to buy something from the market. If there was a reverse bank, then it would become much easier to cope with.
2) Market
I find it extremely difficult to find the parts of the planes I need, and would prefer not to check every ten minutes if they have it, and panic when it turns out I’m missing the bux. This is something I would however accept paying extra bux for.
3) Gifts/friends
I have used the gift system many times before, and think it’s a great idea, but it just needs more interaction. If there was a “neighborhood” of sorts or a flight crew/ guild type, that would be amazing. The only part I can think of is that it would be nice to be able to gift an entire plane all at once, rather than it parts.
Keeping all these complaints in mind though, I find this to be a fun, simple, and easy game, and I will continue to enjoy this game, regardless of my complaints. I would not, however, be opposed to a future update. :)