Planning for a Williams and Jones combo pick

In my 12 team ppr league I have the first pick. My current plan is to go RB 1st then unless I am blown away with the RB available I will likely go WR, WR if Gronk is available then I take him.

Worst case I am entertaining the idea of taking Williams and jones back to back at some point in an effort to lock down the packers backfield. I assume one of those two will get the bulk of the carries with Montgomery going to a pass catcher/utility role in order to try to keep him healthy.

Is this a sound plan and at what point do I target the combo? Draftwizard projects I will have to use my 7th and 8th rd picks.

This is my roster following this strategy

QB Philip Rivers LACBYE 8
RB Todd Gurley LAR BYE 12
RB Lamar Miller HOU BYE 10
WR Mike Evans TB BYE 5
WR Doug Baldwin SEA BYE 7
TE Kyle Rudolph MIN BYE 10
FLX Golden Tate DET BYE 6
DST Seattle Seahawks BYE 7
K Stephen Gostkowski NE BYE 11

WR Jamison Crowder WAS BYE 4
RB Jamaal Williams GB BYE 7
RB Aaron Jones GB BYE 7
WR Marqise Lee JAC BYE 9
RB Bilal Powell NYJ BYE 11
WR Rishard Matthews TEN BYE 8

I guess you did not hear about Marquise Lee before the draft. It looked pretty bad.

No draft was before game