Another perfectly reasonable AST idea

[Cheibriados]

Had a similar cards idea to yours once. Another one I had recently was to divide the cards across the two sects. So for example, Bole/Arrow for Diurnal and Spear/Balance for Nocturnal. Ewer/Spire would be available for both.

The only problem with that is that it would make Noct stance something you're forced to use even though you're severely limiting yourself.