Perhaps, on mature reflection, he would take a different view.

But someday she'd like to write a more meditative, mature reflection on her past.

On mature reflection it was not so unlucky.

We say things that have little to do with what we might say in public, after mature reflection.

But, unlike the clarinet, the flute has a tough time sounding autumnal and mellow; and these sonatas, works of old age, are above all works of mature reflection.