sorting payment groups by number needs to sort numerically
It's a bit distracting sorting on number in that it doesn't sort numerically but alphabetically.
Unfortunately the sequence by default doesn't set the number of digits to 3 or 4 which at least would sort correctly as alpha.
I wonder if tryton shouldn't consider providing a 'natural' sort as payment groups aren't the only difficulty.
https://blog.codinghorror.com/sorting-for-humans-natural-sort-order/