I've been thinking of how to go about which materials to trade with and looking for which ones maybe used least. That way I'm getting mats I'll use lots of while using ones in the trade that I won't use in actual crafting.
A good example is trading for pharmaceutical isolators with a much more common and lesser used material.
I have a rather short list of engineering blueprints that I will use often for my ships.
Dirty drive tuning
Increased fsd range
Charge enhanced Power distributor
Heavy duty bulkheads
Overcharged power plant
Thermal resistant shield boosters
Overcharged Multi-cannons
lightweight sensors and life support
Ok so the list isn't that short but these are generally the blueprints I will use very often. Also I understand (mostly) how the material trading system works. I'm unsure of mats are used less therefore are more available to trading away for more useful (to me) materials
I briefly tried to look at and analyze the recipes for the whole of engineering and felt overwhelmed with how many materials there are and how many recipes there are for modules