My personal recommendation would be to use GIMP to make .gih brushes because you can specify that a layer image be divided into cells for each ‘stamp’.
That way you can see the stamps more easily.
Krita has each stamp on a separate layer so it’s impossible to see them together as a collection on the canvas.
I’ve made two dimensional .gih brushes in GIMP and in krita and I much prefer to use GIMP for it. You can make exactly the same animated brush in krita but the UI/UX at the design/build stage is more pleasant in GIMP.
If you go above two dimensions of control then using additional layers in GIMP becomes necessary. I’ve made four dimensional brushes and that is an interesting experience 