I was thinking some more consumables might be a good gold sink.

Seeing as though there is clairvoyance & vision ward, how about an item for every spell?

clairvoyance = vision ward
heal = health pot
clarity = mana pot
exhaust = boleadoras
ghost = white sheet mini ghost
revive = pheonix down *use on player corpses* *expensive*
smite = remote satalite
teleport = teleport shard
cleanse = vaccine
fortify = car wax *single target turret*
promote = medal of honor
ignite = moltov cocktail *click to use then click location to throw, ignites area*
rally = a flag
flash = lightning in a bottle *click to use then click to flash to location*

It would add an extra element to strategy, especially if a seperate item bar is made for consumables, other then the equipment slots. Most of the items will have to be much more expensive then health/mana pots unless their power can be toned down.