The problem preflop is that even if you put your A2o against random range which is 100%. Take a look that your hand ain't even that much ahead:
Equity Win Tie
UTG 54.93% 52.95% 1.98% { A2o }
UTG+1 45.07% 43.09% 1.98% { random }
But lets say ATo:
Equity Win Tie
UTG 62.72% 61.57% 1.15% { ATo }
UTG+1 37.28% 36.12% 1.15% { random }
You see how big the difference is? You are just putting yourself into trouble with such a hand while there ain't gonna be a lot worse Ax hands and starting to build it up preflop. While might even make mistakes postflop.
What do you think about the thinking process? .) Are there any significant errors?
Well, of course it's somewhat reasonable but do you really expect the opponent to be that aggressive? We can't even be sure that he Limp/Calls preflop and then shows aggression postflop. More often in such situations they rather have a strong made hand. Without knowing the opponent exactly it's hard to expect them always to have any kind of draw there.