>>279691034The way I see it, it was important to show the happy times with other students of same master before shit hit the fan, so there was not much room to include everyone, and Akane was not quite yet the threat that would move Kaisei. And then everything moved too fast with France and timeskip.
If she really nails this competition now, that should put her on Kaisei's map, and give the plot more room for events between competition and students of Issho interaction.