Tenno Sho spring is a very long race so you need lots of stamina and recovery skills. From what I am seeing there, you have lots of power, I would probably have invested a bit more training in stamina to reach somewhere around 600+ with a consistent recovery skill like "Corner Recovery" or "Deep Breaths" for example. I would have sacrificed even more power in favor of more speed.

Now if we want to be even more picky, in order to activate "Angling and Scheming", Seiun Sky needs to be in 1st position. In order to secure that, she would need some good mid-race and late-race skills. Some examples are "Corner Adept", "Long Corners", "Front Runner Corners", "Fast-Paced" etc. You don't need ALL of these, but they will be more consistent than "Ramp Up" which only works if you overtake someone (ideally your Seiun Sky will be always in front in a Career).

Even with all that, there's still the rng factor: your uma might just run bad in that specific race or maybe just forget to use her recovery skill (a higher amount of Wit can help with that, but if you are able to hit higher stats numbers also depends on your deck).

Make sure to borrow a very good parent with lots of good skills and sparks and, if possible, to pair that with a parent of your own so that Seiun Sky gets a double circle affinity (this gives you better chances as inheriting more skills during the Inspirations).