OK, so there is already a stop mode called "Rewind" (in Settings > Playback Settings). If you select that, the playhead will jump back to the beginning of a song when you pause playback during a song.
Then version 3.8 will have the feature to only stop playback at the end of an audio region. Usually your regions start and end on a full measure, so with that function when you hit play again, you will be at the beginning of a new measure.
And then you have the option Damir described. Just tap on an audio region and the playhead will be placed at the beginning of that region.