Are Allen Robinson and DJ Chark WR one's?

I’m In a 10 team .5ppr league(1 QB, 2 RB, 2 WR, and 1 FLEX) and have Allen Robinson and DJ Chark as my main receivers. In this league you usually need to be pretty loaded to win, and that’s why I’m wondering if I should I trade off some of my depth at RB to get a true WR 1 or if Robinson and Chark can get the job done the rest of the way.

RB- Cook, Drake, Robinson, Montgomery, Hines, Mattison
WR- Robinson, Chark, Hilton, Hollywood
TE- Kittle

Good players but they are not top 10 WRs in my opinion…Solid 2s.