Always pick Staff because it gives more Magic ATT while Wand only gives 5% additional Critical Rate for less Magic ATT.
Critical Rate is not a problem when there are many other sources for it.
The attack speeds on both weapons do NOT actually affect the speed at which Evan skills are cast.
Evan do not need to use their class secondary, "Document".
Shields come with Star Force and therefore, more INT, LUK, and Magic ATT.
Deimos Sage Shield recipe is most commonly dropped by Cygnus (Normal) and it is one craft per recipe.
Below are links to some calculator resources:
https://www.patreon.com/MetaCalc
https://brendonmay.github.io/wseCalculator/
Otherwise, the setup that is generally sought after is one of the following:
9 lines of Magic ATT
8 lines of Magic ATT and 1 line of Boss Damage