For a number of years I co-owned and managed a metal fabrication company that specilized in the manufacture of custom metal cabinets, enclosures and control consoles, so I had to deal with the same problem with 4'X8' sheets of expensive SST316 that the majority of our customers required.
Based upon that experience, my recommendation is to first develop a material layout patterning procedure for each cutting that minimzes the number of small waste material drops. This allows you to get the maximum number of usable items from each cutting and results in the largest area of uncut retained reuseable material for storage and later use. This also applies to lengths of preshaped lumber as well.
The next item that is required to take advantage of this new matrial saving procedure is to develop an efficient inventory storage and recording and recovery system for your reuseable in-stock materials that will allow you quickly identify what is available in stock and what will need to be ordered for later jobs.
Finally, depending upon your tradeoff of machine cost vs productivity, I recommend you investigate the availablity of programable cutting machines for cutting your sheet or preshaped materials to your layouts or required lengths and shapes without damaging your reuseable materials.