Who would you team your Okoye with?

With 5 black?  What you want are teams that can do two things for her:

(1) generate yellow to keep her well healed.  This is extra important for you with only 1 yellow cover.

(2) cheap/free powers that deal direct damage ( not tile destruction damage or special tiles damage).  Something like strange, Medusa, bl4deor America are ideal for passive damage.  They will tick every turn when they get going (or more often for strange against goons) and staco okoye's black damage on top.  For active powers you want anything that is cheap and does multiple hits (because each hit will proc okoye). Sabertooth red is ideal.  Cheap aoe powers also work. 

There are literally too many good combos to mention in a brief post.  So feel free to experiment.  You will have lots of fun.  I expect you to come back  gery excited about what a revelation it was.