Keep any 1 drop. [card_link name="power word: feast"] either with [card_link name="frazzled freshman"], or on coin with [card_link name="injured tol'vir"]. It has to hit something to be useful.
[card_link name="dragonmaw overseer"] can be kept either with [card_link name="imprisoned homunculus"] or with a 1/2 curve, or even a 1/coin curve.
[card_link name="Sethekk veilweaver"] should be kept either with a [card_link name="frazzled freshman"] , or with coin a [card_link name="power word: shield"]
[card_link name="high abbess alura"] should only be kept with coin if you feel like going for a highroll