If you go for 10k-10k then your return on invested capital is not as good as with 17k-4k for some time because you need to invest more (and the money cant be spent on players to make you win more, promote, get more money from a higher league etc.).
In the long run however, 10k-10k might be better but the question is...are you going to stay with BB that long...
Thus, there is an optimum somewhere for a given time you will play BB that does not gimp you financially but still generates a good income. The longer you stay, the more this shifts to less bleachers, which is not fortunate because thats usually the first thing you need to build to quickly increase your income with limited resources.