On our App, you have the ability to 'Split by Customer Names' which will group the orders by customer. However, we only ever load the oldest 250 orders. So if certain customers do not fall within that range, you wont see these orders unless you refresh the list to show the next 250 and so on.
For high volume customers, we need the ability to filter for a specific customer and the SO list only display orders for selected customer. It is also important that after completion of 1 order, that the filter is still applied so as to not start loading other customers again.
Wave picking can assist with this, but in the case where there are low and high volume customers mixed in, it doesn't always make sense to create a wave
This is handled in Picking 2.0, which will show how many orders there are per customer regardless of how many total orders require picking.