I think the main area where having those players back will help is keeping the opposing defenses more honest, and potentially stretching the field a bit more.
As you said, it will likely be difficult getting them the ball on longer routes, but it may at least allow for defenses to play a bit differently. They will certainly take some middle route shots here and there, and hope that one of them can get the ball in space and gain some YACs too. Of course Nate Solder's situation will be an important aspect to monitor moving forward, as we have way too many issues on the offensive line already as it is.
It obviously didn't help that Josh Boyce dropped THREE more passes today either, as they did attempt to get some speed involved outside of the "slow white six" (Amendola, Edelman, Collie, Hooman, Devlin, Mulligan) short to intermediate routes.