I really think that raid weapons and gears need something really special and unique, something that "classic" stuff found in quests will never have.
This is a weapon suggestion:
Mother tree (longbow), a weapon for casters Arcane Archer.
- Spell Power (OR/AND insight/quality/special)
- Spell Lore (OR/AND insight/quality/special)
- Spell Focus (OR/AND insight/quality/special)
- Deific Focus
- Proc on hit and offensive spells (suggestion for Brazen Brilliance like the staff of irian -->
https://ddowiki.com/page/Item:Staff_of_Irian OR earthgrab procs)
- Special Effect depending on the current element used (corrosive, flaming, frost, shock, force) with your elemental arrow (suggestions :AOE damages/ DOT damages / Control effects as stun, freeze, earthgrab / Curses ... on weapon hit/crit/vorpal and/or offensive spells. All effects DC are based on your EVOCATION DC and ALL DAMAGES are depending of your elemental arrow damage Dice)
- Conjure a special Returning Arrow ( I REALLY think that ALL NAMED Bows in the game should have a "conjure returning special arrow" at least all lvl 20+ bows)
The idea is here, hope you like it