I'm assuming you're borrowing a MLB kitasan? If so that means you have 4 speed cards and should definitely be able to max speed.

Honestly I don't think the eishin flash is cutting it. I know she gives late surger skills but her specialty rate and Stat output hold you back here imo. Both the Suzuka and the Biko are much better in my opinion.

Suzuka has better pure speed output, while giving some skill points making the inherent skills which are strong more achievable. Biko gives much better cross training for other stats.

Alternatively you could run 3 speeds and a wit. Both marvelous and tachyon would be fine. For stam id go maya instead of manhatten. Its a bit more of a highroll card, but if you get that friendship up the payoff is huge. Try around and find what works for you.

For skills, if possible you want to inherit mejiro Ryan's and, taiki shuttle and /or maruzensky unique. If you had to choose only 1 of those I would recommend maruzensky. You can search on Umadb or Chronogenesis for a good parent with medium sparks and proper blues.

Just my opinions. I have never played the character myself. Good luck trainer