(1) It is important to have a set of values one strives for and also to be reasonable sure that that set in fact leads to good results. One might hear a promise from people he respects that "If you do such and such a practice on a constant basis, such and such good things will be the result". Often these are false promises.

(2) In terms of areas of study  also, it is important to identify areas of study that deliver what they promise. As Steven Weinberg [theory of the unified weak and electromagnetic interaction between elementary particles,] has pointed out on the unreasonable ineffectiveness of philosophy, and the unreasonable effectiveness of Mathematics. Here he suggested that certain fields deliver much more than what they promise and other fields deliver considerably less that what they promise.

(3) Though the Rambam did emphasize learning the Oral and Written Law, Physics and Metaphysics, my feeling is that philosophy today is much worse than a waste of time. It positively ruins one' common sense. [Of course the Rambam was anyway only referring to the Metaphysics of Aristotle, not just to any book that talk about that subject.]

(4) I used to think that at least Enlightenment Philosophy did bring about a remarkable change --representative government until it became clear to me that it did no such thing. Enlightenment philosophers did intend to take power from kings and princes and give it to the the pseudo intellectuals intellectuals like psychologists. But they did not come up with any good idea about representative government. On the contrary they came up with a  host of really bad ideas the ruined Western society the more they took root. You can blame the Islamic invasion of England and Europe to the pernicious lie about the "noble savage." that was thought u by Enlightenment philosopher.

(5) Musar also seems to promise much more than it is able to deliver. That is the study of Medieval books of Ethics. This was made into a mass movement by Reb Israel Salanter, but it does not seem that it deliver the promised result--good midot (good character).

(6) Calvin was the one that thought up and institute representative government, not any philosopher.