Hi. I just created a guide on how to supercharge your Alloy Smelters with the PackagedAuto mod, allowing you to parallelize as many recipes as you want, with as many Alloy Smelters as you want! If you find any errors, or got anything to add, please leave a comment below!
Can also do something similar using Steve's Factory Manager for the packs that actually have SFM, not too hard either.