How the FUCK do you get stronger at this game?

I've been playing for about two weeks now, I can beat most of the careers for the Umas I've got, and I've got a few cards saved up, but I only have two 3* Umas, I'm not even close to having 30k Carats to pull, so I'm not getting any more Umas or merges anytime soon, and I certainly don't feel like I'm getting much stronger.

It's all about Sparks for inheritance, okay, so I need to get 1100 Stamina so I can start getting Stamina sparks. Except if I try for 1100 Stamina my run dies because I can't get enough Stamina without making huge sacrifices in other stats and skipping optional races.

So, am I just meant to get 600 Speed 600 Stamina and pray for that 5% chance for a 3* Spark to proc? Is that really all I can do?

>>718470129
I could eat a.. uhh..

>>718466000
>stamina went up by 69

>>717269494
Sex with suzuka silence

>>717141375
Im farming for 3* speed and I want to bang suzuka so fucking hard but unfortunately Im stuck with taiki shuttle and her god awful VO. The second option is king halo but getting good stats on her is way harder