We are made to stock and we use forecast to drive demand. When we run MRP, we got a job suggestion for every sales order which is not helpful. Rather, we would like to see one job suggestion for the forecast which includes sales orders.
one of the setup at part level is Days of Supply, which aggregate sales qty for this part into one job up to the period that you will define in it, e.g if you put 90 days MRP will look 90 days ahead from the first demand need which is basically based on sales release ShipByDate and raise one job or more based on Min and Max Lot Size
Another way to affect this is to adjust the min/max/multiple to make the jobs the size you are accustomed to running.
I will say that the mixed forecast/sales order environment is a bit of a sticky wicket - the system does apply some logic when calculating how to meet demand.