Very good points you made here. It took me some time to actually find an answer to it. So I would like to throw some light on the "natural desires". Natural desires are natural emotions that are found in everyone, only in a different ratio. For eg :- greed, crave for attention, to feel appreciated, sadness, jealousy, anger etc. These can be called natural but what you stated above isn't natural. That is what differentiates you from the others. You have a desire of caring for people and want to know things but if it was natural, everyone would carry it in the same proportion. Similarly, everyone can draw, sing, write, act etc but some can draw, write, sing and act better then others. It doesn't mean it's natural. It's their own quality. What is natural is a child's attitude to always look for adventure and happiness in things. Natural is common. Your desire isn't common.

Yes, being happy is what really matters and finding your purpose helps in it. And one can never determine a moment when no improvements can be made. You can always improve.