It seems to me like Hinoka is in the deck because...
1. Hoshido does not have many good options for fliers, and Ryoma does not allow you to mix with other colors cooperatively.
2. She's a 40 support for Ryoma 1, which could randomly save you an orb considering how long he can wait before promoting.
3. At 60 power, 70 with Kamui M, she can make a decent backup attacker late-game.
4. Cost 1 Hinoka is in here already for a reliable early 40 attacker, so running 4 and 4 means you can draw into critical hits more easily.
To me, it's less about using her ability and more about what else she can do for the deck.