For me, I would use Roundup + Enlist + generic Pursuit.  That would work for me. That may not work for you in your situation.  Here, Pursuit would give good residual of grass, and works good on pigweed - that is redroot and smooth pigweed.  I will not comment on Waterhemp, as I don't see it.  (Waterhemp is a member of the pigweed family.)   

Just saying what works for me, not what you should do.