I once had a very experienced pilot tell me that when doing aerobatics, one should always be "two-mistakes" high, especially if trying something new. That was high enough to screw up a maneuver (mistake no. 1) and screw up the recovery attempt (mistake no. 2), and still have altitude left to sort it out.
By and large, history would suggest a floor of 3,000 ft AGL is about two-mistakes high!