If I'm crafting something, that requires material A (eg. steel), and there is no material A in direct form, workshop will automatically consume stored in the workshop space or in the my inventory loot item providing A. Cool, but if this item also provides materials B, C etc., AFAIK these are wasted in the process - disappear. Am I right? It shouldn't be that way. A spare material from consumed item should be preserved IMO. There is a workaround, but far from smooth: I can drop an item on the ground and using construction GUI dismantle it into prime factors. My second suggestion would be an easy/fast way to process at once all stored in the workshop loot into primal materials.
Currently - absurdal things may happen, as I experienced recently, if crafted item in the same time requires and provides same material and I'm trying to make many copies one by one, let's say some utility mixture at chemical table.
Let's say item X requires A and B materials while provides A. I have not enough "bare" A material around, so workshop begins to consume stored loot... including just made X items. So in such case I can't make more than one copy of this item at a time - if I try to make the second, first one is consumed to craft it, etc. ad infinitum - at the end I will have a single copy of that item. Absurd.