A bit like Old Smokey, whose learned posts I always read with awe, I learned to fly in 1965, but have rather fewer hours than he does. Listen to him - his reasonableness test is a great tool to employ in aviation. When taxying in, if the situation permits, try running the question; 'How could we could have done that sector better?' There is always something.
Cheers,
mcdhu
PS I even forgot to refuel once!