hero equipment question

I'm planning to run a curse necro with barbs and MoP, and potentially a OotV blood necro (or just plain orders on any/N)

my question is would it be beneficial at all to run most of my heroes with spear/offhand (20/20 for whatever attribute they use most)? this would allow me to take advantage of the orders/blood bond/barbs/MoP while still using the caster heroes that i want. with barbs/orders even non-spec spear is adding a good bit of damage.

thoughts?

10%hct spear and appropriate enchanting mod(orders) (mm) or other(+30hp(curses), doesn't matter that much
offhand 20/20 in attribute hero is using
this way u will have a 28% chance on half casts, and half casts are very beneficital