Disproportionate sizes between letters and numbers in math-mode

Is it just me that thinks that numbers in math-mode are disproportionately sized in comparison to letters? I am using the font Tex Gyre Termes. It is particularly noticeable in subscripts. For example:

$A_{rs}, A_{1s}, A_{r2}$

which gives

Is there anyone else that is slightly vexed by this? If so, is there a solution to normalise the size between numbers and letters?