I am not aware of staves giving stronger bonuses than wands. In my experience, dual wielding wands was always far superior in terms of stat bonuses, and still is in DOS 2. For example, I have Turner of the Tides, a legendary source weapon, that gives a whopping +2 INT. The most I've ever heard of is +9 on a staff. I have heard of wands giving +5/+2 INT/MEM before, and not to mention, with memory as it is if you haven't pumped literally every point you have into it, then you won't have enough spells to constantly cast. So staves are in a really bad spot right now IMO, although contrary to popular opinion, I've found that they are totally crazy for hybrid builds. My favorite build, the Mega Mage (1 warfare/1 scoundrel/1 marksman/1 pyro/1 hydro/1 aero/1 geo/1 necro) uses staves to enable Battle Stomp, allowing you to act whenever enemies are shielded by pesky magic armor, but are lacking physical. Still, I feel that staves could use a boost. +1 to lowering the cooldown and boosting the AP cost, since wands feel straight up stronger for everything that isn't a hybrid.
