Sorry, but that’s just 50 days? That’s insane. 3 5*s and Prisma Cosmos is really good. Also, you’ve got 6 random drops of Golden Sumo. I honestly almost don’t believe you actually.
In terms of servants to raise, finish of Karna, and then the ones that really stick out to me are Kintoki (he just nukes things), David (party-wide evasion), and Georgios (3 turn taunt).