My perspective is that the Universe doesn't distinguish between "big" and "little". Whether you're putting forth a desire to have chocolate cake for dessert tonight, or you want to add $10K to your income this month, I think it's all the same to the U. The difference is that you see a difference, you think one is harder to get than the other, and that has an effect on how successful you are at manifesting what you want in your life.
There's a saying among Abers that you can create a castle as easily as you can a button.
But what I'm getting at, in terms of your initial question, is that you might want to try not worrying about separating out your "true desires" from all the various "smaller" things that you want. Because if you can align yourself to whatever it is that you want, whether big or small, whether earth-shattering or small and mundane, you'll create it in your life.
And, yes, the word "want" can have a negative connotation. But it doesn't have to - it depends on your emotion when you use the word.