Why is it that almost every person who posts a team like this is fairly well stacked. You're obviously covered at QB & RB. Receiver is another question all together.
Gardner will have a fine year. Booker should do well in Chicago if all of the ball sharing doesn't hurt his numbers (they have 4 or 5 starting WRs on that team). Johnnie Morton will be a nice addition if he stays healthy in KC. Driver could step into the #1 receiving role in GB if Glenn stays hurt. Lelie won't have an impact this year. He's behind two solid starters, and there are others there who can play the third receiver. Rookies almost always (Randy Who?) have a rough first year. It's a lot to learn.
You might want to think about trading M. Bennett or T. Henry (which ever seems to get more interest in your league) for a solid WR. Usually you don't do such things, but your RB situation is solid. If you don't get a GOOD (Keyshawn, Kevin Johnson, Tim Brown, that level) offer, let it ride. Some of your receivers are bound to step up and have a really solid year.