I really think Bell will be hard to replace. My eyes are on Turner and how, or if he comes back from his injuies. He was a bright, promising prospect at one point in time, but it seems so were many, many other WRs (Curenski stands out; there were others before, and after, such as Khiry).
With Burtch and Reilly we are talking about something like 20 career receptions between the two of them? Moore's another name you could throw into that mix. DPE is proven as a returner. As a receiver he came on late, and they have big plans for him, but he has to make a big 2nd year leap.
So, yeah, outside of Westerkamp I don't think we have proven carry the load guys. Even Westerkamp -- very solid and productive, but not a outside speed threat like Bell, or a red zone threat like Purify. Without those, the whole offense suffers. I'm very much not sold on the WRs this year.
If they do live up to the billing, it will take guys like Irons & Tolbert & DPE to break out. Heck, all the veterans, too: Allen, Burtch, Reilly, Moore, Turner. All of this is a projection. I don't agree that they are extremely deep, nor that they are more than solid at the top. Just a lot of bodies whose careers are open ended in where they fall on the spectrum: (Curenski? Meno Holt? Niles Paul? Enunwa/Bell? Etc).