I'd like to suggest it not being possible for people to do damage to the hot air balloons. Every time I go in one people shoot at the balloon and I have to sit there and patch it so it doesn't crash.
I'm not sure why it's possible to do damage to the hot air balloons but not the mini heli and regular heli when people shoot at it but it gets a little irritating when I have to wait to repair the hot air balloon I'm using.