with MK, you normaly need the aura of the AM, because he hasn't that much mana. and to buy always Lesser Clarity Potion will have a effect of your army. with normal strategies, i wouldn't recommend the MK

two points as an example for disadvantages:
-no brillance aura(less mana for your caster)
-no WE to creep(no militia creep or with 2 more militias)
but i will add for you some strategies with MK first in 1on1

as i said, i will update that guide as often as i can
but you have brought me on a idea. i will add some 2on2 strategies to the guide too

there i use the MK as first hero very often
and i can promise, that i will do my best to make my orc guide as good as this