[Perdition]

The gem staves are a recent addition, a series of polearms that are all spelledge weapons that also provide ele ATK to a weapon in particular corresponding to the gem the staff uses. These have been great additions to the game, but they've also stepped on some toes and made some things redundant.

For example, God Rod from Priest makes it so if you have a staff subtype weapon equipped, you can specifically cast Mercalan spells with it as a proper casting tool. However, with the staff weapons, why bother? Now you can get a light staff that not only gives you Light ATK, but it's a proper casting tool for ALL spells. The only real niche here with god rod is that you can use it with a heavier staff that can potentially get 20+ weight two handed bonus without having to do some jank like giant gene your weapon.

Still, I don't think that's enough to warrant God Rod remaining as it is. I think that instead, God Rod should be changed to perhaps provide bonus light attack or a boost in spell power to Mercalan domain spells while you have a staff subtype weapon equipped. 

Furthermore, I think it's time for staff subtype weapons to simply act as casting tools by default. At the very least, weapons like Overgrown Staff and Eternal Servitude are very clearly arcane weapons, the latter being dropped by a Necromancer that assumedly uses the weapon himself and casts spells of his own--it even grants you access to a spell this necromancer uses while not being a casting tool. 

I don't think changes like these would cause any balance issues either. Not using a tome for casting comes with the downside of losing 5 skill slots, which is actually quite relevant for most mages and it's something that's almost always taken into consideration even when it comes to using the gem staves mentioned at the start of my post.