Thanks for your help with my question
Out of your 3 DEF's, I'd go with Seattle for sure. The Patriots defense is, well, the Patriots defense. They'll certainly bend but may not break. Look at the garbage scores they gave up to the Colts last week. The Titans are playing against Drew Brees and the Saints, need I say more?
As far as your WR/FLEX situation is concerned, I'd go with Marshall over Helu AND Smith.
The Redskins will probably be playing from behind and also try to take advantage of a weak NE secondary (Moss could have a big day). Marshall gets consistent targets and, along with the rest of MIA, has been playing well lately.
Smith started out the season on fire, but in the past few weeks he has since returned to last year's Smith. I wouldn't be surprised if he failed to score 10 fantasy points again
this week (he had 5 catches for only 66 yards the last time they played ATL).
So, this would leave you with choosing between Smith and Helu... Out of those two, I'd probably go with Helu because of the reasons that you stated previously. He should be even more involved in the passing game now that Fred Jackson is suspended.
Hope this helps!