What makes twinking a caster "great"

[WarpathEQ]

Velium crystal staff off rip that's your Venomous axe for casters...lvl 1 nuke proc. Combine it with some HP/AC standard twink gear and you got yourself a battle caster for the early game.

Beyond that certainly a GCD item would be a key item to equip a caster with, tons of options and varying price levels.

Clicky Items, whether its mana free DPS or utility items, lots of good clickies to obtain on casters that will beef up your efficiency/utility.

To me the key difference is casters don't have as much impactful middle tier gear (things like fungi tunic and weapons that boost DPS) so a lot of the melee equivalant twinking is expensive. Things like Z-heart, manastone, manna robe, Chocker of the Wretched. etc. can make a caster wildly strong they just put a much larger hole in the pocketbook.