I am surprised that everybody seems happy with the size of the minus sign when it is used to negate a quantity.
The minus sign has two different yet related functions: subtraction and negation. When you use it as a subtraction binary operator as in $3-4$ of $f-g$ it looks perfect, the minus sign is as wide as the plus sing in $3+4$. When you write $3+(-4)$ or $x^{-n}$ it looks way too big (especially in the exponent).
Note that TeX (or LaTeX?) correctly reduces the spacing when it believes we use the unary negation operator but does not change the symbol to a shorter one. TeX and LaTeX are systems that put a lot of effort in correct spacing and sizing, I am surprised people are happy with the current situation of the negative sign. I have found the following discussion here: Is there a designated symbol for the negative sign in, say, -16? but the proposed solution textminus does not work in math mode and siunitx does not seem to be part of the standard package distributions anymore and other solutions are more like hacks.
-1
exponent term when it's used to denote the inverse of some object, have a look at Matrix Inverse symbol.$^{-}2$
to distinguish them from$0-2$
but I don't see that other than school level introductions to negative numbers.