Hi JB. Although most commercial coffee machines have 58mm baskets certainly doesnt mean narrower baskets are in any way inferior. If anything, a narrower and deeper basket can be more forgiving.
Ideally it would be nice to see a video of your pour but it sounds to me like youre getting a pretty decent shot out of your equipment. If it tastes good I wouldnt be too concerned about the volume.
You could try a slightly finer grind and lighter tamp to see how you go. You could also try different beans.