@Madhungarian and
@Futuramille...
Air mode is completely different than Flight Modes. Flight Modes include Angle, Horizon, and when NEITHER of those 2 are enabled it is AUTOMATICALLY in Acro. This has nothing to do with Air Mode, and it can be on or off in ALL of the Flight modes depending on the BF configuration for Air Mode. I am guessing both of you have Air Mode permanently enabled in BF on the Configuration page slider, I have my slider turned off and have assigned a switch to it because I have some reasons to do so.
When you have Air Mode enabled and you are in Acro, it only says AIR in the display, if you had Air Mode turned off, or turned off by switch position, then the display would actually show "ACRO" in the display. When the display says Angle, Horizon or possibly STAB, air mode is still on for you guys.
It is funny how BF works sometimes, I have seen a few odd things when I updated to OpenTX 2.3.1 and got the new LUA scripts. Sometimes it is a bug, sometimes it is intended operation for whatever reason, but when it is different than it used to be, you need to research and test all over again to be sure.
Wayno52 is correct on both accounts, expo will help a little to smooth minor stick movements out, but mostly it is about practice and just getting better on the stick inputs to get smoother. With practice you will get smoother and smoother over time.