While the CS ticket itself didn't profit (due to the specific combination of legs hitting a 30% strike rate on exact scores suggests the model's underlying algorithms for calculating team strength are very calibrated,)

You should really give betting singles a chance to build a profitable model. With combos, everything becomes way more a game of chance, and it's nearly impossible to get a bet sample that is big enough to remove all the variance.

I get it though, low stakes risk and potential high reward is far more attractive than higher stakes with no chance to hit a big jackpot but more boring grinding it out.

At the same time, you are up at the moment so well done so far!