3) I know the number is really 21million*10^8 or whatever. But that is still fixed and the size of the bitcoin economy (hopefully) isn't fixed. The idea is that it will grow right? So that means that the value of bitcoins will have to change over time which isn't ideal. A currency that has 0 inflation/deflation is the most ideal right?
A currency with a fixed supply has 0 inflation/deflation by definition.
You are probably referring to price inflation/deflation, which is a seperate phenomenon and is unimportant as long as there is no monetary inflation/deflation. Even if you wanted to, there is no meaningful way to do it. Just look at how fudged the CPI numbers are.