Triple air LitII with it’s Lightning Strike provides the best DPS, though it won’t break all possible DR like Mineral II does. The Artificer class surely changed a lot about this, but you don’t always have one available for DR breaking purposes like for example in the guild raids.

You can check different combinations for GS items/weapons on http://www.iro.umontreal.ca/~delallea/ddo/shroud/index.php

Edit: Indeed I was thinking of Lightning II, thank you Jan for the correction.

Yep, for Greensteel would go for Lightning 2 as a nice dps’er, The epic Longbow of Earth I showed you suits most other situations, then it is just about chest loot, other epic and crafted for situational but the Longbow of Earth covers you for pretty much all bosses where the lit 2 might fall down.

You will then benefit from having 2 greensteel items, one should be a pure hp item to give you +45 hp (pretty cheap to make) the other would ideally be an existential stalemate (+6 wis with certain combo) of conc opp (when get hit have chance to regain hp and sp) this item should give you 150sp/50sp and 100sp at each level, can be mixed up/amended dependant upon other gear.

To use both use will need an essense of cleansing so 20 shroud runs for reward.

The location to put these really depend on other gear layout, whilst you are doing the shrouds for ingre can obviously fill other slots so it should become clearer as to where to put.