1.)With the new implement of focus to healing gears, most of these items are now BiS for the mage class.

2.)Specifically wand, even though cleric wands rarely drop, the game's forcibly making top tier players to drop down to 10-men raids such as GP to grind for the Wand of Excess in order to provide maximum stats. The other option is to grind out 540 inscribes in order to gain more spell power.

These two known issues being said, Trion should do something about it.
i.) you can choose to buff HK mage gear, or
ii.) you can choose to give more SP from Intellegence (1.25~1.5) so that high Int items actually mean something, or
iii.) increase the soft cap and hard cap of Spell Crit, so that going above 1k spell crit can actually be viable in raid scheme.

There are multiple solutions, but changing drop rates and forcing mages to roll on cleric gears is not an option.