I wanted to add my insights on the Weapon dmg(Wdm) vs Caster problem, im currently at 200 hours played and i spend alot of that time theorycrafting and testing things 😮
I think we can all agree that its a multifaceted issue that makes Wdm chars so much weaker, Trinkets, Gear, Skill orbs and Stats in general are all heavy caster-favored.
Spells have skill orbs that Weapons attacks do not and all they get for compensation is Weapon Mastery that is kind of expensive and underwhelming.
Weapon attacks usually lack range, pierce, speed, projectile numbers, additional modifiers, homing and just raw power compared to most spells.
Another very minor advantage for casters is that there are 3 classes that give int when leveled up, but given time it will add up.
Intellect is a superior stat giving the trifecta of SP, crit and critdmg and all caster gear give much better bonuses aswell, 40% innate castspeed on chest and 20% mana cost reduction on boots.
Furthermore spellcasters also get 2 exponentially scaling stats, while wdm chars have none afaik, those being cooldown reduction and mana cost reduction.
F.e. 50% "actual" cooldown reduction (that you do need a bit of castspeed to reach i know) is a 100% damage increase and you can even reach >80% cdr which would be a 500% damage multiplier (at the same increased mana cost ofc.)
Attackspeed enchants are only a 10% increase which is underwhelming to say the least and you kind of lose the stats from your weaponslot since you basically must have Crushing/Vulnerable and most characters also use a 2hander.
Many weaponattacks have underwhelming scalings like Quickshot f.e. doing only 60% Wdm with 0 pierce, Dual Daggers is basically the only exception of an actual decent weapon.
The number of Trinkets is higher for casters and they have a very generalized dmg multiplier of 36x from trinkets, while for wdm builds that number is 11.5x.