What is worth hanging on to for possible trades

So generally speaking, what kinds of items are worth hanging on to for trading purposes?

I’ve reached the point where I’ve got lots of duplicate items spread over a number of mules and filled stash panels, and I’m in the process of trying to clear through some of the duplicated items.

Which brings me to my question, other than Blueprints, mythic/legendary items, and monster infrequents with good affixes, what is actually worth hanging on to for possible trade purposes? Are (most) epic items (As an example, I’ve got about half a dozen storm scions and probably nearly that many Lichguards along with shed loads of other epic duplicates) generally not worth stockpiling?

Thanks in advice for your advice/opinions

Have a look in these threads and see what other people are looking for.

http://www.grimdawn.com/forums/showthread.php?t=67564

MATERIALS. SCRAP. IRON. UGDENBLOOMS. …fucking blooms man

I cannot emphasize this enough. EVERYTHING which first seems inconsequential when you begin become of utmost value in the end game

Scavenged Plating.

Some (most?) people would want to have thousands of it to craft Stoneplate Greaves and hope for a few well rolled double rares.