Giving heroes just a focus

Not worth it.
You're sacrificing mods on the wand that are vital in a lot of hard mode areas.

e.g.: Health mods and casting time and recharge time The only mod I would consider vital is +20% Enchants for the appropriate builds. A small amount of extra health is completely useless in most cases and HSR/HCT on a wand only gives +8% improvement to each on average, which is hardly exceptional if this turns out to be a large effect.

EDIT:

# of 1s cast time spells cast in 1 min vs master of damage:

23/31/30 casts in 1 min with flatbow
28/32/31 casts in 1 min with spear
36/36/35 casts in 1 min weaponless

I thought I may have biased the results a bit by using just 1 spell, so I loaded up Sousuke's spell bar with all 1s cast fire spells instead of just flare.

Averages about 15% improvement in cast frequency going weaponless over the spear. I'll give a tentative thumbs up to the tactic for heroes that need to spam spells, aren't recharge rate limited, and aren't in need of +20% enchants, where it should edge out HCT/HSR by a healthy margin.

Why no 40/40 set? Or, in this case, why no 40/20/20 Enchanting staff? Simply going weapon vs weaponless cuts the # of random factors down to 1, which is always the way to test things. Furthermore, HCT/HSR both act in different ways from this extra spell casting delay, and different builds would shift the balance between the three one way or another (e.g. HSR mods would have been completely useless in this test because all skills recharge so fast). Given the raw data, anyone who wants to calculate the particular effect on their build in comparison to HCT/HSR is able to do so.

To drill down my previous numbers to an easily understandable formula, it appears that you can estimate that a weapon increases aftercast time between spells by approximately 20% of your weapon attack rate, assuming its a linear curve (I suspect that it isn't linear but exhaustively testing weapons to disprove that is rather futile since no one is running hornbows on caster heroes).

Not worth it.
You're sacrificing mods on the wand that are vital in a lot of hard mode areas.

e.g.: Health mods and casting time and recharge time Utter rubbish, GW is too easy as it is.

We use heroes without any weapons of any sort (10 heroes, two people) for the Deep HM, and breeze through it, since no need to change out and the initial area can be completed in a few minutes.

Not worth it.
You're sacrificing mods on the wand that are vital in a lot of hard mode areas.

e.g.: Health mods and casting time and recharge time considering half my heroes don't even have weapons and i've vq'd and done HM missions easily, i hardly consider it vital.