At level 2 the max win bonus I can give is 30k and that's also what I give them for each competition.
So yes, I lose 1.2k per league win, but the past 3 CL matches alone gave me 270k income after bonus. With 6 out of 7 league matches won this makes 7.2k loss and 380k income from cup makes 642.8k income from prize money alone after win bonus and not calculating ticket income. I don't really see a reason not to set it at my current stage.