I would say that to improve one's financial situation, one should seek more sources of income; however, one thing about the standard of living is that the more income and financial stability one gains, the level of financial living also increases. The main goal is to concentrate on saving and investing, because if you focus on improving your financial living, you may end up not saving or investing at all.
Exactly when you earn more through different streams of income, the standard of living increases alongside that's to say depending on one source of income can't create a balance for ones financial stability, but sometimes some person's savings plan can't improve their standard of living which is why you find them taking koans and being in debt. But having a multi streams income can ensbke one achieve that.
I think the standard of living also needs to be improved, I mean it as a form of appreciation for yourself after working hard, and of course by maintaining the principle of saving and investing. If you focus too much on saving and investing without enjoying it, someone will look stingy to yourself, the point is don't go overboard. If you have several sources of income, with good financial management, someone can easily manage all their desires.
People who succeed in saving and investing certainly have a good understanding of financial management, they are no longer tempted by various urges to spend money that is not needed. Those who are careless, who fail to manage their finances after successfully having several sources of income will never change, and may fail to prepare for a better future.