To make it clear, begining From The Ashes rather make economics harder for you. So I would suggest doing it in parallel of the main game just to make it more challenging - right to the point with above-0 income. That feels like a hell of accomplishment. After that you may just balance buildings there in a way it makes you slow profit or sometimes expense. And enjoy the main game.
In that case you play 2 almost separate games in parallel.
But personally I wouldn’t mind getting rich from completing the quest. The game allows you to get rich if you want it anyway.
Edit: be cautious though following my advice as I haven’t finished neither maingame nor FtA yet. Just so far cannot see how my natural playing tactics could ruin anything.