I think the most likely of the big 4 skill players that could be there at 12 out of Chase, Smith, Pitts and Waddle is Smith. There are going to be teams that are scared of his size, but if he's there and the other three are gone, I think they have to take him, he was a monster in college, so forget about his size. DJax got the same scrutiny when he came out, which is why the Eagles got him in the second round.
A lot will depend on if the first four picks are all QBs, which they could be, we know the first three will be. Atlanta at 4 could be taking the last QB, be it Lance or Fields or if they go elsewhere I don't think they are going receiver, Pitts is possible, they could also trade back with Carolina or Detroit, which would like a QB. Bengals at 5 would be stupid not to draft Sewell. Miami is certainly taking 1 of the 4, likely Chase, then I think the Lions at 7 could go receiver having just lost their best receiver in free agency but they also need a QB. I think the 8th pick, whether it is the Falcons or the Panthers could be a spot for Pitts, but it could also go defense. I think the Broncos at 9 and the Cowboys at 10 go defense as well and certainly won't pick a receiver. The Giants are the wildcard. They have needs at a lot of positions, if they don't select a receiver, then it is possible that 2 of the 4 could be there for the Eagles at 12, but at least 1 should be.